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ooooo-youwillsee/leetcode | 0064-Minimum-Path-Sum/cpp_0064/Solution1.h | <gh_stars>10-100
//
// Created by ooooo on 2020/2/13.
//
#ifndef CPP_0064__SOLUTION1_H_
#define CPP_0064__SOLUTION1_H_
#include <iostream>
#include <vector>
using namespace std;
/**
* dp[i][j] = cur_num + min(dp[i-1][j] + dp[i][j-1])
*/
class Solution {
public:
int minPathSum(vector<vector<int>> &grid) {
if (grid.empty()) return 0;
int m = grid.size(), n = grid[0].size();
vector<vector<int>> dp(m, vector<int>(n));
dp[0][0] = grid[0][0];
for (int i = 1; i < m; ++i) {
dp[i][0] = dp[i - 1][0] + grid[i][0];
}
for (int i = 1; i < n; ++i) {
dp[0][i] = dp[0][i - 1] + grid[0][i];
}
for (int i = 1; i < m; ++i) {
for (int j = 1; j < n; ++j) {
dp[i][j] = grid[i][j] + min(dp[i - 1][j], dp[i][j - 1]);
}
}
return dp[m - 1][n - 1];
}
};
#endif //CPP_0064__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 1817-Finding the Users Active Minutes/cpp_1817/Solution1.h | <filename>1817-Finding the Users Active Minutes/cpp_1817/Solution1.h
/**
* @author ooooo
* @date 2021/4/11 15:54
*/
#ifndef CPP_1817__SOLUTION1_H_
#define CPP_1817__SOLUTION1_H_
#include <iostream>
#include <vector>
#include <unordered_map>
#include <unordered_set>
#include <set>
#include <stack>
#include <numeric>
#include <queue>
using namespace std;
class Solution {
public:
vector<int> findingUsersActiveMinutes(vector<vector<int>> &logs, int k) {
unordered_map<int, unordered_set<int>> m;
for (auto &log :logs) {
m[log[0]].insert(log[1]);
}
unordered_map<int, int> x;
for (auto &e : m) {
x[e.second.size()]++;
}
vector<int> ans(k, 0);
for (int i = 0; i < k; ++i) {
ans[i] = x[i + 1];
}
return ans;
}
};
#endif //CPP_1817__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 1609-Even Odd Tree/cpp_1609/Solution1.h | <filename>1609-Even Odd Tree/cpp_1609/Solution1.h
/**
* @author ooooo
* @date 2020/10/11 13:41
*/
#ifndef CPP_1609__SOLUTION1_H_
#define CPP_1609__SOLUTION1_H_
#include "TreeNode.h"
bool isEvenOddTree(TreeNode *root) {
queue<TreeNode *> q;
q.push(root);
int level = 0;
while (!q.empty()) {
bool incr = level % 2 == 0;
int val = incr ? 0 : 10000000;
for (int size = q.size(); size > 0; size--) {
TreeNode *node = q.front();
q.pop();
if (incr) {
if (node->val <= val || node->val % 2 == 0) return false;
} else {
if (node->val >= val || node->val % 2 == 1) return false;
}
val = node->val;
if (node->left) q.push(node->left);
if (node->right) q.push(node->right);
}
level++;
}
return true;
}
#endif //CPP_1609__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0572-Subtree-of-Another-Tree/cpp_0572/Solution1.h | //
// Created by ooooo on 2020/1/3.
//
#ifndef CPP_0572_SOLUTION1_H
#define CPP_0572_SOLUTION1_H
#include "TreeNode.h"
class Solution {
public:
bool isSameTree(TreeNode *s, TreeNode *t) {
if (!s && !t) return true;
if (!s || !t) return false;
return s->val == t->val && isSameTree(s->left, t->left) && isSameTree(s->right, t->right);
}
bool isSubtree(TreeNode *s, TreeNode *t) {
if (!s) return false;
return isSameTree(s, t) || isSubtree(s->left, t) || isSubtree(s->right, t);
}
};
#endif //CPP_0572_SOLUTION1_H
|
ooooo-youwillsee/leetcode | 0049-Group-Anagrams/cpp_0049/Solution1.h | <filename>0049-Group-Anagrams/cpp_0049/Solution1.h
//
// Created by ooooo on 2020/2/11.
//
#ifndef CPP_0049__SOLUTION1_H_
#define CPP_0049__SOLUTION1_H_
#include <iostream>
#include <vector>
#include <unordered_map>
using namespace std;
/**
* 哈希表
*/
class Solution {
public:
vector<vector<string>> groupAnagrams(vector<string> &strs) {
unordered_map<string, vector<string>> map;
for (int i = 0; i < strs.size(); ++i) {
string key = string(strs[i]);
sort(key.begin(), key.end());
map[key].push_back(strs[i]);
}
vector<vector<string>> ans;
for (auto &entry: map) {
ans.push_back(entry.second);
}
return ans;
}
};
#endif //CPP_0049__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 1816-Truncate Sentence/cpp_1816/Solution1.h | /**
* @author ooooo
* @date 2021/4/11 15:50
*/
#ifndef CPP_1816__SOLUTION1_H_
#define CPP_1816__SOLUTION1_H_
#include <iostream>
#include <sstream>
using namespace std;
class Solution {
public:
string truncateSentence(string s, int k) {
istringstream in(s);
string w;
string ans = "";
while (k && (in >> w)) {
ans += w;
k--;
if (k > 0) {
ans += " ";
}
}
return ans;
}
};
#endif //CPP_1816__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0098-Validate-Binary-Search-Tree/cpp_0098/Solution2.h | <reponame>ooooo-youwillsee/leetcode<gh_stars>10-100
//
// Created by ooooo on 2019/11/1.
//
#ifndef CPP_0098_SOLUTION2_H
#define CPP_0098_SOLUTION2_H
#include <iostream>
#include "TreeNode.h"
using namespace std;
/**
* 比较左孩子的val和当前节点的值
*/
class Solution {
private:
TreeNode *prev;
bool help(TreeNode *node) {
if (node == NULL) {
return true;
}
if (!help(node->left)) {
return false;
}
if (this->prev && this->prev->val >= node->val) {
return false;
}
this->prev = node;
return help(node->right);
}
public:
bool isValidBST(TreeNode *root) {
this->prev = NULL;
return help(root);
}
};
#endif //CPP_0098_SOLUTION2_H
|
ooooo-youwillsee/leetcode | lcof_059-2/cpp_059-2/Solution1.h | <gh_stars>10-100
//
// Created by ooooo on 2020/4/25.
//
#ifndef CPP_059_2__SOLUTION1_H_
#define CPP_059_2__SOLUTION1_H_
#include <iostream>
#include <deque>
#include <unordered_map>
using namespace std;
class MaxQueue {
public:
deque<int> q, help;
MaxQueue() {
q.clear();
help.clear();
}
int max_value() {
if (q.empty()) return -1;
return help.front();
}
void push_back(int value) {
q.push_back(value);
while (!help.empty() && help.back() < value) help.pop_back();
help.push_back(value);
}
int pop_front() {
if (q.empty()) return -1;
int ret = q.front();
q.pop_front();
if (help.front() == ret) help.pop_front();
return ret;
}
};
#endif //CPP_059_2__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 1221-Split-a-String-in-Balanced-Strings/cpp_1221/Solution1.h | //
// Created by ooooo on 2020/2/3.
//
#ifndef CPP_1221__SOLUTION1_H_
#define CPP_1221__SOLUTION1_H_
#include <iostream>
using namespace std;
class Solution {
public:
int balancedStringSplit(string s) {
int R_count = 0, ans = 0;
for (int i = 0; i < s.size(); ++i) {
if (s[i] == 'R') R_count++;
else if (s[i] == 'L') R_count--;
if (R_count == 0) ans += 1;
}
return ans;
}
};
#endif //CPP_1221__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0242-Valid-Anagram/cpp_0242/Solution2.h | //
// Created by ooooo on 2019/11/1.
//
#ifndef CPP_0242_SOLUTION2_H
#define CPP_0242_SOLUTION2_H
#include <iostream>
#include <string>
#include <algorithm>
#include <map>
using namespace std;
class Solution {
public:
bool isAnagram(string s, string t) {
map<char, int> m1;
map<char, int> m2;
for (auto i : s) {
map<char, int>::iterator it = m1.find(i);
if (it == m1.end()) {
m1[i] = 1;
} else {
m1[i] = it->second + 1;
}
}
for (auto i : t) {
map<char, int>::iterator it = m2.find(i);
if (it == m1.end()) {
m2[i] = 1;
} else {
m2[i] = it->second + 1;
}
}
return m1 == m2;
}
};
#endif //CPP_0242_SOLUTION2_H
|
ooooo-youwillsee/leetcode | 0496-Next-Greater-Element-I/cpp_0496/Solution1.h | <reponame>ooooo-youwillsee/leetcode
//
// Created by ooooo on 2020/1/5.
//
#ifndef CPP_0496_SOLUTION1_H
#define CPP_0496_SOLUTION1_H
#include <iostream>
#include <vector>
using namespace std;
/**
* 暴力破解
*/
class Solution {
public:
vector<int> nextGreaterElement(vector<int> &nums1, vector<int> &nums2) {
vector<int> res;
for (auto num1: nums1) {
int find = -1;
for (int i = 0; i < nums2.size(); ++i) {
if (nums2[i] == num1) {
// 向nums1的后面找
for (int j = i + 1; j < nums2.size(); ++j) {
if (nums2[j] > num1) {
find = nums2[j];
break;
}
}
break;
}
}
res.push_back(find);
}
return res;
}
};
#endif //CPP_0496_SOLUTION1_H
|
ooooo-youwillsee/leetcode | 0145-Binary-Tree-Postorder-Traversal/cpp_0145/TreeNode.h | <filename>0145-Binary-Tree-Postorder-Traversal/cpp_0145/TreeNode.h
/**
* @author ooooo
* @date 2020/9/25 23:33
*/
#ifndef CPP_0145__TREENODE_H_
#define CPP_0145__TREENODE_H_
#include <iostream>
#include <vector>
#include <stack>
using namespace std;
struct TreeNode {
int val;
TreeNode *left;
TreeNode *right;
TreeNode() : val(0), left(nullptr), right(nullptr) {}
TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}
};
#endif //CPP_0145__TREENODE_H_
|
ooooo-youwillsee/leetcode | 0377-Combination Sum IV/cpp_0377/Solution1.h | <filename>0377-Combination Sum IV/cpp_0377/Solution1.h<gh_stars>10-100
/**
* @author ooooo
* @date 2021/4/24 08:34
*/
#ifndef CPP_0377__SOLUTION1_H_
#define CPP_0377__SOLUTION1_H_
#include <iostream>
#include <vector>
#include <unordered_map>
using namespace std;
class Solution {
public:
int dfs(vector<int> &nums, int target) {
if (memo.find(target) != memo.end()) return memo[target];
if (target == 0) return memo[target] = 1;
if (target < 0) return memo[target] = 0;
int ans = 0;
for (int i = 0; i < nums.size(); i++) {
ans += dfs(nums, target - nums[i]);
}
return memo[target] = ans;
}
unordered_map<int, int> memo;
int combinationSum4(vector<int> &nums, int target) {
return dfs(nums, target);
}
};
#endif //CPP_0377__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0073-Set Matrix Zeroes/cpp_0073/Solution1.h | <gh_stars>10-100
/**
* @author ooooo
* @date 2020/10/11 20:09
*/
#ifndef CPP_0073__SOLUTION1_H_
#define CPP_0073__SOLUTION1_H_
#include <iostream>
#include <vector>
using namespace std;
class Solution {
public:
void setZeroes(vector<vector<int>> &matrix) {
if (matrix.empty()) return;
int m = matrix.size(), n = matrix[0].size();
vector<bool> rows(m), cols(n);
for (int i = 0; i < m; ++i) {
for (int j = 0; j < n; ++j) {
if (matrix[i][j] == 0) {
rows[i] = true;
cols[j] = true;
}
}
}
for (int i = 0; i < m; ++i) {
for (int j = 0; j < n; ++j) {
if (rows[i] || cols[j]) {
matrix[i][j] = 0;
}
}
}
}
};
#endif //CPP_0073__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0046-Permutations/cpp_0046/Solution1.h | <reponame>ooooo-youwillsee/leetcode
//
// Created by ooooo on 2020/2/10.
//
#ifndef CPP_0046__SOLUTION1_H_
#define CPP_0046__SOLUTION1_H_
#include <iostream>
#include <vector>
#include <unordered_set>
using namespace std;
class Solution {
public:
void dfs() {
if (marked.size() == nums.size()) {
ans.push_back(added);
return;
}
for (int i = 0; i < nums.size(); ++i) {
if (marked.count(nums[i])) continue;
marked.insert(nums[i]);
added.push_back(nums[i]);
dfs();
marked.erase(nums[i]);
added.pop_back();
}
}
vector<int> nums;
vector<vector<int>> ans;
unordered_set<int> marked;
vector<int> added;
vector<vector<int>> permute(vector<int> &nums) {
this->nums = nums;
dfs();
return ans;
}
};
#endif //CPP_0046__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | lcof_033/cpp_033/Solution1.h | <reponame>ooooo-youwillsee/leetcode<filename>lcof_033/cpp_033/Solution1.h<gh_stars>10-100
//
// Created by ooooo on 2020/3/21.
//
#ifndef CPP_033__SOLUTION1_H_
#define CPP_033__SOLUTION1_H_
#include <iostream>
#include <vector>
using namespace std;
class Solution {
public:
bool help(int l, int r) {
if (l >= r) return true;
int i = r - 1;
while (i >= 0) {
if (postorder[i] < postorder[r]) {
for (int j = 0; j < i; ++j) {
if (postorder[j] > postorder[r]) return false;
}
break;
}
i--;
}
return help(l, i) && help(i + 1, r - 1);
}
vector<int> postorder;
bool verifyPostorder(vector<int> &postorder) {
if (postorder.empty()) return true;
this->postorder = postorder;
return help(0, postorder.size() - 1);
}
};
#endif //CPP_033__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0559-Maximum Depth of N-ary Tree/cpp_0559/Solution2.h | //
// Created by ooooo on 2019/12/29.
//
#ifndef CPP_0599_SOLUTION2_H
#define CPP_0599_SOLUTION2_H
#include "Node.h"
class Solution {
public:
int maxDepth(Node *root) {
if (!root) return 0;
int max = 0;
for (int i = 0; i < root->children.size(); ++i) {
int depth = maxDepth(root->children[i]);
max = std::max(max, depth);
}
return max + 1;
}
};
#endif //CPP_0599_SOLUTION2_H
|
ooooo-youwillsee/leetcode | 0227-Basic Calculator II/cpp_0227/Solution1.h | /**
* @author ooooo
* @date 2021/3/11 09:25
*/
#ifndef CPP_0227__SOLUTION1_H_
#define CPP_0227__SOLUTION1_H_
#include <iostream>
#include <vector>
#include <stack>
using namespace std;
class Solution {
public:
void calc(stack<long long> &numStack, stack<char> &opStack) {
int x = numStack.top();
numStack.pop();
int y = numStack.top();
numStack.pop();
char c = opStack.top();
opStack.pop();
if (c == '+') {
numStack.push(y + x);
} else if (c == '-') {
numStack.push(y - x);
} else if (c == '*') {
numStack.push(y * x);
} else if (c == '/') {
numStack.push(y / x);
}
}
/*
* 测试用例
* "3+2*2"
"1-1+1"
"1-1-1"
"2*3+4"
* */
int calculate(string s) {
int i = 0, n = s.size();
stack<long long> numStack;
stack<char> opStack;
int sign = 1;
while (i < n) {
while (i < n && s[i] == ' ') i++;
if (i >= n) break;
if (s[i] == '-') {
sign = -sign;
i++;
opStack.push('+');
continue;
}
if (s[i] == '+' || s[i] == '*' || s[i] == '/') {
opStack.push(s[i]);
i++;
continue;
}
long long num = 0;
while (i < n && s[i] >= '0' && s[i] <= '9') {
num = num * 10 + (s[i] - '0');
i++;
}
numStack.push(num * sign);
sign = 1;
if (!opStack.empty() && (opStack.top() == '*' || opStack.top() == '/')) {
calc(numStack, opStack);
}
}
while (numStack.size() > 1) {
calc(numStack, opStack);
}
return numStack.top();
}
};
#endif //CPP_0227__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0021-Merge-Two-Sorted-Lists/cpp_0021/Solution2.h | <reponame>ooooo-youwillsee/leetcode
//
// Created by ooooo on 2020/1/23.
//
#ifndef CPP_0021__SOLUTION2_H_
#define CPP_0021__SOLUTION2_H_
#include "ListNode.h"
/**
* 使用原先的节点 （效率高）
*/
class Solution {
public:
ListNode *mergeTwoLists(ListNode *l1, ListNode *l2) {
ListNode *dummyHead = new ListNode(0), *cur = dummyHead;
while (l1 && l2) {
if (l1->val == l2->val) {
ListNode *temp1 = l1->next;
ListNode *temp2 = l2->next;
cur->next = l1;
cur = cur->next;
cur->next = l2;
cur = cur->next;
l1 = temp1;
l2 = temp2;
} else if (l1->val < l2->val) {
ListNode *temp1 = l1->next;
cur->next = l1;
cur = cur->next;
l1 = temp1;
} else {
ListNode *temp2 = l2->next;
cur->next = l2;
cur = cur->next;
l2 = temp2;
}
}
while (l1) {
ListNode *temp1 = l1->next;
cur->next = l1;
cur = cur->next;
l1 = temp1;
}
while (l2) {
ListNode *temp2 = l2->next;
cur->next = l2;
cur = cur->next;
l2 = temp2;
}
return dummyHead->next;
}
};
#endif //CPP_0021__SOLUTION2_H_
|
ooooo-youwillsee/leetcode | 0861-Score After Flipping Matrix/cpp_0861/Solution2.h | <gh_stars>10-100
/**
* @author ooooo
* @date 2020/12/7 16:07
*/
#ifndef CPP_0861__SOLUTION2_H_
#define CPP_0861__SOLUTION2_H_
#include <iostream>
#include <math.h>
#include <vector>
using namespace std;
class Solution {
public:
int matrixScore(vector<vector<int>> &A) {
int m = A.size(), n = A[0].size();
int ans = m * (1 << (n - 1));
vector<int> cols(n, 0);
for (int j = 1; j < n; ++j) {
for (int i = 0; i < m; ++i) {
if (A[i][0] == 0) {
// need flip
cols[j] += 1 - A[i][j];
} else {
cols[j] += A[i][j];
}
}
int k = max(cols[j], m - cols[j]);
ans += k * (1 << (n - j - 1));
}
return ans;
}
};
#endif //CPP_0861__SOLUTION2_H_
|
ooooo-youwillsee/leetcode | 0977-Squares-of-a-Sorted-Arrays/cpp_0977/Solution1.h | <reponame>ooooo-youwillsee/leetcode<filename>0977-Squares-of-a-Sorted-Arrays/cpp_0977/Solution1.h
//
// Created by ooooo on 2020/1/7.
//
#ifndef CPP_0977_SOLUTION1_H
#define CPP_0977_SOLUTION1_H
#include <iostream>
#include <vector>
#include <cmath>
using namespace std;
/**
* sort
*/
class Solution {
public:
vector<int> sortedSquares(vector<int> &A) {
for (int i = 0; i < A.size(); ++i) {
A[i] = pow(A[i], 2);
}
sort(A.begin(), A.end());
return A;
}
};
#endif //CPP_0977_SOLUTION1_H
|
ooooo-youwillsee/leetcode | 0160-Intersection-of-Two-Linked-Lists/cpp_0160/Solution1.h | <gh_stars>10-100
//
// Created by ooooo on 2020/1/23.
//
#ifndef CPP_0160__SOLUTION1_H_
#define CPP_0160__SOLUTION1_H_
#include "ListNode.h"
#include <unordered_set>
/**
* 哈希表
*/
class Solution {
public:
ListNode *getIntersectionNode(ListNode *headA, ListNode *headB) {
unordered_set<ListNode *> s;
while (headA) {
s.insert(headA);
headA = headA->next;
}
while (headB) {
if (s.count(headB)) return headB;
headB = headB->next;
}
return nullptr;
}
};
#endif //CPP_0160__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0590-N-ary-Tree-Postorder-Transversal/cpp_0590/Solution1.h | //
// Created by ooooo on 2020/1/3.
//
#ifndef CPP_0590_SOLUTION1_H
#define CPP_0590_SOLUTION1_H
#include "Node.h"
class Solution {
public:
void dfs(Node *node, vector<int> &vec) {
if (!node) return;
for (auto child: node->children) {
dfs(child, vec);
}
vec.push_back(node->val);
}
vector<int> postorder(Node *root) {
vector<int> vec;
dfs(root, vec);
return vec;
}
};
#endif //CPP_0590_SOLUTION1_H
|
ooooo-youwillsee/leetcode | lcof_046/cpp_046/Solution2.h | <gh_stars>10-100
//
// Created by ooooo on 2020/4/2.
//
#ifndef CPP_046__SOLUTION2_H_
#define CPP_046__SOLUTION2_H_
#include <iostream>
#include <unordered_map>
#include <vector>
using namespace std;
/**
* dp[i] = dp[i+1] + ( valid ？ dp[i+2] : 0 )
*/
class Solution {
public:
int valid(int i) {
if (i + 1 >= s.size() || s[i] == '0' || s[i] > '2') return false;
if (s[i] == '1') return true;
return s[i] == '2' && s[i + 1] < '6';
}
string s;
int translateNum(int num) {
this->s = to_string(num);
int len = s.size();
vector<int> dp(len + 1);
dp[len] = 1;
for (int i = len - 1; i >= 0; --i) {
dp[i] = dp[i + 1] + (valid(i) ? dp[i + 2] : 0);
}
return dp[0];
}
};
#endif //CPP_046__SOLUTION2_H_
|
ooooo-youwillsee/leetcode | 0129-Sum Root to Leaf Numbers/cpp_0129/TreeNode.h | <reponame>ooooo-youwillsee/leetcode
/**
* @author ooooo
* @date 2020/10/29 09:31
*/
#ifndef CPP_0129__TREENODE_H_
#define CPP_0129__TREENODE_H_
#include <iostream>
#include <vector>
using namespace std;
struct TreeNode {
int val;
TreeNode *left;
TreeNode *right;
TreeNode(int x) : val(x), left(NULL), right(NULL) {}
};
#endif //CPP_0129__TREENODE_H_
|
ooooo-youwillsee/leetcode | lcof_007/cpp_007/Solution1.h | //
// Created by ooooo on 2020/3/7.
//
#ifndef CPP_007__SOLUTION1_H_
#define CPP_007__SOLUTION1_H_
#include "TreeNode.h"
#include <unordered_map>
class Solution {
public:
TreeNode *dfs(TreeNode *node, int l, int r) {
if (l > r) return nullptr;
int root_value = preorder[i++];
int root_index = in_map[root_value];
node = new TreeNode(root_value);
node->left = dfs(node->left, l, root_index - 1);
node->right = dfs(node->right, root_index + 1, r);
return node;
}
vector<int> preorder;
unordered_map<int, int> in_map;
int i = 0;
TreeNode *buildTree(vector<int> &preorder, vector<int> &inorder) {
for (int j = 0, len = inorder.size(); j < len; ++j) {
in_map[inorder[j]] = j;
}
this->preorder = preorder;
return dfs(nullptr, 0, inorder.size() - 1);
}
};
#endif //CPP_007__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | lcof_041/cpp_041/Solution2.h | //
// Created by ooooo on 2020/3/26.
//
#ifndef CPP_041__SOLUTION2_H_
#define CPP_041__SOLUTION2_H_
#include <iostream>
#include <queue>
using namespace std;
class MedianFinder {
private:
vector<int> nums;
public:
/** initialize your data structure here. */
MedianFinder() {
}
void addNum(int num) {
if (nums.empty()) nums.emplace_back(num);
else nums.insert(lower_bound(nums.begin(), nums.end(), num), num);
}
double findMedian() {
int mid = nums.size() / 2;
return (nums.size() & 1) == 0 ? (nums[mid - 1] + nums[mid]) / 2.0 : nums[mid];
}
};
#endif //CPP_041__SOLUTION2_H_
|
ooooo-youwillsee/leetcode | lcof_049/cpp_049/Solution3.h | <filename>lcof_049/cpp_049/Solution3.h
//
// Created by ooooo on 2020/4/6.
//
#ifndef CPP_049__SOLUTION3_H_
#define CPP_049__SOLUTION3_H_
#include <iostream>
#include <vector>
using namespace std;
/**
* dp
*/
class Solution {
public:
int nthUglyNumber(int n) {
vector<int> nums(n, 1);
int count = 1, num_2 = 0, num_3 = 0, num_5 = 0;
while (count < n) {
int min_v = min({nums[num_2] * 2, nums[num_3] * 3, nums[num_5] * 5});
nums[count] = min_v;
// 可能会出现 3 * 2 = 6 和 2 * 3 = 6
if (nums[num_2] * 2 == nums[count]) num_2++;
if (nums[num_3] * 3 == nums[count]) num_3++;
if (nums[num_5] * 5 == nums[count]) num_5++;
count++;
}
return nums[n - 1];
}
};
#endif //CPP_049__SOLUTION3_H_
|
ooooo-youwillsee/leetcode | lcof_010-2/cpp_010-2/Solution1.h | <reponame>ooooo-youwillsee/leetcode
//
// Created by ooooo on 2020/3/9.
//
#ifndef CPP_010_2__SOLUTION1_H_
#define CPP_010_2__SOLUTION1_H_
#include <iostream>
#include <vector>
using namespace std;
/**
* dp[n] = dp[n-1] + dp[n-2]
*/
class Solution {
public:
int numWays(int n) {
if (n ==0) return 1;
if (n == 1 || n == 2) return n;
int a = 1, b = 2, c = 0;
for (int i = 3; i <= n; ++i) {
c = (a + b) % 1000000007;
a = b;
b = c;
}
return c;
}
};
#endif //CPP_010_2__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 1812-Determine Color of a Chessboard Square/cpp_1812/Solution1.h | /**
* @author ooooo
* @date 2021/4/11 07:57
*/
#ifndef CPP_1812__SOLUTION1_H_
#define CPP_1812__SOLUTION1_H_
#include <iostream>
#include <vector>
using namespace std;
class Solution {
public:
bool squareIsWhite(string s) {
return (s[1] - (s[0] - 'a')) % 2 == 0;
}
};
#endif //CPP_1812__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0461-Hamming-Distance/cpp_0461/Solution2.h | //
// Created by ooooo on 2020/2/6.
//
#ifndef CPP_0461__SOLUTION2_H_
#define CPP_0461__SOLUTION2_H_
#include <iostream>
#include <sstream>
using namespace std;
/**
* ^操作， i & (i-1) --> 去掉最后一个1
*/
class Solution {
public:
int hammingDistance(int x, int y) {
int res = x ^y, ans = 0;
while (res) {
ans += 1;
res = res & (res - 1);
}
return ans;
}
};
#endif //CPP_0461__SOLUTION2_H_
|
ooooo-youwillsee/leetcode | 1629-Slowest Key/cpp_1629/Solution1.h | /**
* @author ooooo
* @date 2020/11/15 09:39
*/
#ifndef CPP_1629__SOLUTION1_H_
#define CPP_1629__SOLUTION1_H_
#include <iostream>
#include <vector>
#include <unordered_map>
#include <unordered_set>
using namespace std;
class Solution {
public:
char slowestKey(vector<int> &releaseTimes, string keysPressed) {
vector<pair<int, char>> ans;
int prev_time = 0;
for (int i = 0; i < keysPressed.size(); ++i) {
ans.push_back(make_pair(releaseTimes[i] - prev_time, keysPressed[i]));
prev_time = releaseTimes[i];
}
sort(ans.begin(), ans.end(), greater<pair<int, char>>());
return ans[0].second;
}
}
#endif //CPP_1629__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0917-Reverse-Only-Letters/cpp_0917/Solution1.h | <reponame>ooooo-youwillsee/leetcode
//
// Created by ooooo on 2020/2/1.
//
#ifndef CPP_0917__SOLUTION1_H_
#define CPP_0917__SOLUTION1_H_
#include <iostream>
using namespace std;
/**
* 双指针
*/
class Solution {
public:
string reverseOnlyLetters(string S) {
if (S.size() <= 1) return S;
int left = 0, right = S.size() - 1;
while (true) {
while (left <= right && !isalpha(S[left])) left++;
while (right >= left && !isalpha(S[right])) right--;
if (left > right) break;
swap(S[left++], S[right--]);
}
return S;
}
};
#endif //CPP_0917__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0017-Letter-Combinations-of-a-Phone-Number/cpp_0017/Solution1.h | <reponame>ooooo-youwillsee/leetcode
//
// Created by ooooo on 2020/2/7.
//
#ifndef CPP_0017__SOLUTION1_H_
#define CPP_0017__SOLUTION1_H_
#include <iostream>
#include <vector>
using namespace std;
class Solution {
public:
vector<vector<string>> letters = {
{"a", "b", "c"},
{"d", "e", "f"},
{"g", "h", "i"},
{"j", "k", "l"},
{"m", "n", "o"},
{"p", "q", "r", "s"},
{"t", "u", "v"},
{"w", "x", "y", "z"},
};
vector<string> ans;
void help(string s, string &digits, int i) {
if (i == digits.size()) {
ans.push_back(s);
return;
}
for (auto letter: letters[digits[i] - '2']) {
help(s + letter, digits, i + 1);
}
}
vector<string> letterCombinations(string digits) {
if (digits.empty()) return {};
ans.clear();
help("", digits, 0);
return ans;
}
};
#endif //CPP_0017__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0120-Triangle/cpp_0120/Solution2.h | <filename>0120-Triangle/cpp_0120/Solution2.h
//
// Created by ooooo on 2019/12/16.
//
#ifndef CPP_0120_SOLUTION2_H
#define CPP_0120_SOLUTION2_H
#include <iostream>
#include <vector>
#include <climits>
using namespace std;
/**
* 自底向上
*
* res[i] = min (res[i] , res[j]) + res[row][i]
*/
class Solution {
public:
int minimumTotal(vector<vector<int>> &triangle) {
vector<int> res(triangle.size() + 1, 0);
for (int i = triangle.size() - 1; i >= 0; --i) {
for (int j = 0; j < triangle[i].size(); ++j) {
res[j] = min(res[j], res[j + 1]) + triangle[i][j];
}
}
return res[0];
}
};
#endif //CPP_0120_SOLUTION2_H
|
ooooo-youwillsee/leetcode | 0226-Invert-Binary-Tree/cpp_0226/Solution1.h | <gh_stars>10-100
//
// Created by ooooo on 2020/9/15.
//
#ifndef CPP_0226_SOLUTION1_H
#define CPP_0226_SOLUTION1_H
#include "TreeNode.h"
class Solution {
public:
TreeNode *invertTree(TreeNode *root) {
if (!root) return nullptr;
TreeNode *rightNode = root->right;
root->right = invertTree(root->left);
root->left = invertTree(rightNode);
return root;
}
};
#endif //CPP_0226_SOLUTION1_H
|
ooooo-youwillsee/leetcode | 0018-4Sum/cpp_0018/Solution1.h | <filename>0018-4Sum/cpp_0018/Solution1.h
//
// Created by ooooo on 2019/11/1.
//
#ifndef CPP_0018_SOLUTION1_H
#define CPP_0018_SOLUTION1_H
#include <iostream>
#include <vector>
#include <set>
#include <algorithm>
using namespace std;
/**
* 两层循环， 加上双指针
*/
class Solution {
public:
vector<vector<int>> fourSum(vector<int> &nums, int target) {
vector<vector<int>> res;
if (nums.size() < 4) {
return res;
}
sort(nums.begin(), nums.end());
set<vector<int>> set;
for (int i = 0; i < nums.size() - 3; ++i) {
for (int j = i + 1; j < nums.size() - 2; ++j) {
int k = j + 1;
int p = nums.size() - 1;
while (k < p) {
int n = nums[i] + nums[j] + nums[k] + nums[p];
if (n < target) {
k += 1;
} else if (n > target) {
p -= 1;
} else {
vector<int> vec = {nums[i], nums[j], nums[k], nums[p]};
set.insert(vec);
k += 1;
p -= 1;
}
}
}
}
for (auto item : set) {
res.push_back(item);
}
return res;
}
};
#endif //CPP_0018_SOLUTION1_H
|
ooooo-youwillsee/leetcode | 1473-Paint House III/cpp_1473/Solution1.h | <gh_stars>10-100
/**
* @author ooooo
* @date 2021/5/4 09:15
*/
#ifndef CPP_1473__SOLUTION1_H_
#define CPP_1473__SOLUTION1_H_
#include <vector>
#include <iostream>
using namespace std;
class Solution {
public:
/**
dp[m][n][target] 表示第m个房子，涂第n个颜色，为target的neighborhood的值
*/
int minCost(vector<int> &houses, vector<vector<int>> &cost, int m, int n, int target) {
vector<vector<vector<int>>> dp(m, vector<vector<int>>(n + 1, vector<int>(target + 1, INT_MAX / 2)));
// 没有涂色
if (houses[0] == 0) {
for (int j = 1; j <= n; j++) {
dp[0][j][1] = cost[0][j - 1];
}
} else {
dp[0][houses[0]][1] = 0;
}
for (int i = 1; i < m; i++) {
for (int j = 1; j <= n; j++) {
for (int k = 1; k <= target; k++) {
// 没有涂色
if (houses[i] == 0) {
dp[i][j][k] = min(dp[i][j][k], dp[i - 1][j][k] + cost[i][j - 1]);
for (int p = 1; p <= n; p++) {
if (p != j) {
dp[i][j][k] = min(dp[i][j][k], dp[i - 1][p][k - 1] + cost[i][j - 1]);
}
}
} else {
// 当前涂的颜色必须是house[i]
if (j != houses[i]) continue;
dp[i][j][k] = min(dp[i][j][k], dp[i - 1][j][k]);
for (int p = 1; p <= n; p++) {
if (p != j) {
dp[i][j][k] = min(dp[i][j][k], dp[i - 1][p][k - 1]);
}
}
}
}
}
}
int ans = INT_MAX / 2;
for (int j = 1; j <= n; j++) {
ans = min(ans, dp[m - 1][j][target]);
}
return ans == INT_MAX / 2 ? -1 : ans;
}
};
#endif //CPP_1473__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0744-Find-Smallest-Letter-Greater-Than-Target/cpp_0744/Solution2.h | //
// Created by ooooo on 2020/1/20.
//
#ifndef CPP_0744__SOLUTION2_H_
#define CPP_0744__SOLUTION2_H_
#include <iostream>
#include <vector>
using namespace std;
/**
* loop
*/
class Solution {
public:
char nextGreatestLetter(vector<char> &letters, char target) {
for (auto c: letters) {
if (c > target) return c;
}
return letters[0];
}
};
#endif //CPP_0744__SOLUTION2_H_
|
ooooo-youwillsee/leetcode | 0605-Can-Place-Flowers/cpp_0605/Solution1.h | /**
* @author ooooo
* @date 2021/1/1 09:57
*/
#ifndef CPP_0605__SOLUTION1_H_
#define CPP_0605__SOLUTION1_H_
#include <iostream>
#include <vector>
using namespace std;
class Solution {
public:
bool canPlaceFlowers(vector<int> &f, int n) {
if (n == 0) return true;
int x = f.size();
if (x == 1 && f[0] == 0 && n == 1) return true;
for (int i = 0; i < x; i++) {
if (f[i] == 0) {
bool can = false;
if (i == 0 && i + 1 < x && f[i + 1] == 0) can = true;
else if (i == x - 1 && i - 1 >= 0 && f[i - 1] == 0) can = true;
else if (i + 1 < x && i - 1 >= 0 && f[i - 1] == 0 && f[i + 1] == 0) can = true;
if (can) {
n--;
f[i] = 1;
if (n == 0) return true;
}
}
}
return n == 0;
}
};
#endif //CPP_0605__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | lcof_031/cpp_031/Solution1.h | <gh_stars>10-100
//
// Created by ooooo on 2020/3/19.
//
#ifndef CPP_031__SOLUTION1_H_
#define CPP_031__SOLUTION1_H_
#include <iostream>
#include <vector>
#include <stack>
using namespace std;
class Solution {
public:
bool validateStackSequences(vector<int> &pushed, vector<int> &popped) {
stack<int> s;
for (int i = 0, j = 0, len = popped.size(); i < len;) {
int pop_val = popped[i];
while (s.empty() || s.top() != pop_val) {
if (j == len) return false;
s.push(pushed[j++]);
}
s.pop();
i++;
}
return true;
}
};
#endif //CPP_031__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0720-Longest-Word-in-Dictionary/cpp_0720/Solution1.h | <filename>0720-Longest-Word-in-Dictionary/cpp_0720/Solution1.h<gh_stars>10-100
//
// Created by ooooo on 2020/1/14.
//
#ifndef CPP_0720__SOLUTION1_H_
#define CPP_0720__SOLUTION1_H_
#include <iostream>
#include <vector>
#include <unordered_map>
using namespace std;
/**
* 超时
*/
class Solution {
public:
string ans = "";
void dfs(string s, int len, unordered_map<int, vector<string>> m) {
vector<string> words = m[len];
if (words.empty()) {
// 不满足关系说明已经查找完毕 和ans作比较
if (ans.size() < s.size()) {
ans = s;
} else if (ans.size() == s.size() && s < ans) {
ans = s;
}
return;
}
for (int i = 0; i < words.size(); ++i) {
if (s == words[i].substr(0, len - 1)) {
dfs(words[i], len + 1, m);
} else {
// 不满足关系说明已经查找完毕 和ans作比较
if (ans.size() < s.size()) {
ans = s;
} else if (ans.size() == s.size() && s < ans) {
ans = s;
}
}
}
}
string longestWord(vector<string> &words) {
unordered_map<int, vector<string>> m;
for (const auto &word: words) {
int len = word.size();
if (m.count(len)) {
m[len].push_back(word);
} else {
m[len] = {word};
}
}
dfs("", 1, m);
return ans;
}
};
#endif //CPP_0720__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0279-Perfect-Squares/cpp_0279/Solution1.h | //
// Created by ooooo on 2020/2/23.
//
#ifndef CPP_0279__SOLUTION1_H_
#define CPP_0279__SOLUTION1_H_
#include <iostream>
#include <vector>
#include <unordered_set>
using namespace std;
/**
* dfs timeout
*/
class Solution {
public:
void dfs(int n, int count) {
if (n == 0) {
ans = min(ans, count);
return;
}
for (int i = 0; i < nums.size(); ++i) {
if (nums[i] > n) continue;
dfs(n - nums[i], count + 1);
}
}
vector<int> nums;
int ans = INT_MAX;
int numSquares(int n) {
for (int i = int(sqrt(n)); i >= 1; --i) {
nums.push_back(i * i);
}
dfs(n, 0);
return ans;
}
};
#endif //CPP_0279__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 1356-Sort-Integers-by-The-Number-of-1-Bits/cpp_1356/Solution1.h | /**
* @author ooooo
* @date 2020/11/6 20:38
*/
#ifndef CPP_1356__SOLUTION1_H_
#define CPP_1356__SOLUTION1_H_
#include <iostream>
#include <vector>
using namespace std;
class Solution {
public:
vector<int> sortByBits(vector<int> &arr) {
auto fn = [](int n) {
int i = 0;
while (n) {
i++;
n = n & (n - 1);
}
return i;
};
sort(arr.begin(), arr.end(), [&](int x, int y) {
int c1 = fn(x), c2 = fn(y);
return c1 == c2 ? x < y : c1 < c2;
});
return arr;
}
};
#endif //CPP_1356__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0836-Rectangle-Overlap/cpp_0836/Solution1.h | /**
* @author ooooo
* @date 2020/9/30 10:19
*/
#ifndef CPP_0836__SOLUTION1_H_
#define CPP_0836__SOLUTION1_H_
#include <iostream>
#include <vector>
using namespace std;
class Solution {
public:
bool isRectangleOverlap(vector<int> &rec1, vector<int> &rec2) {
return !(
rec1[2] <= rec2[0] || // left
rec1[3] <= rec2[1] || // bottom
rec1[0] >= rec2[2] || // right
rec1[1] >= rec2[3]); // top
}
};
#endif //CPP_0836__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0117-Populating-Next-Right-Pointers-in-Each-Node-II/cpp_0117/Solution1.h | /**
* @author ooooo
* @date 2020/9/28 09:19
*/
#ifndef CPP_0117__SOLUTION1_H_
#define CPP_0117__SOLUTION1_H_
#include "Node.h"
class Solution {
public:
Node *connect(Node *root) {
if (!root) return root;
queue<Node *> q;
q.push(root);
vector<vector<Node *>> rows;
while (!q.empty()) {
vector<Node *> row;
for (int i = 0, len = q.size(); i < len; ++i) {
auto node = q.front();
q.pop();
row.emplace_back(node);
if (node->left) q.push(node->left);
if (node->right) q.push(node->right);
}
rows.emplace_back(row);
}
for (auto &row :rows) {
for (int i = 0; i < row.size() - 1; ++i) {
row[i]->next = row[i + 1];
}
}
return root;
}
};
#endif //CPP_0117__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0088-Merge-Sorted-Array/cpp_0088/Solution1.h | <filename>0088-Merge-Sorted-Array/cpp_0088/Solution1.h
//
// Created by ooooo on 2019/12/5.
//
#ifndef CPP_0088_SOLUTION1_H
#define CPP_0088_SOLUTION1_H
#include <iostream>
#include <vector>
using namespace std;
class Solution {
public:
void merge(vector<int> &nums1, int m, vector<int> &nums2, int n) {
if (nums1.empty() && nums2.empty()) return;
vector<int> target(m + n);
for (int i = 0, j = 0, k = 0; i < m || j < n; k++) {
if (i == m) {
target[k] = nums2[j];
j++;
continue;
}
if (j == n) {
target[k] = nums1[i];
i++;
continue;
}
if (nums1[i] <= nums2[j]) {
target[k] = nums1[i];
i++;
} else {
target[k] = nums2[j];
j++;
}
}
for (int l = 0; l < m + n; ++l) {
nums1[l] = target[l];
}
}
};
#endif //CPP_0088_SOLUTION1_H
|
ooooo-youwillsee/leetcode | 1773-Count Items Matching a Rule/cpp_1773/Solution1.h | /**
* @author ooooo
* @date 2021/3/14 14:52
*/
#ifndef CPP_1773__SOLUTION1_H_
#define CPP_1773__SOLUTION1_H_
#include <iostream>
#include <vector>
#include <unordered_map>
#include <unordered_set>
#include <set>
#include <stack>
#include <numeric>
#include <queue>
using namespace std;
class Solution {
public:
int countMatches(vector<vector<string>> &items, string ruleKey, string ruleValue) {
int ans = 0;
for (auto &item: items) {
if (ruleKey == "type" && ruleValue == item[0]) {
ans++;
} else if (ruleKey == "color" && ruleValue == item[1]) {
ans++;
} else if (ruleKey == "name" && ruleValue == item[2]) {
ans++;
}
}
return ans;
}
};
#endif //CPP_1773__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 1546-Maximum Number of Non-Overlapping Subarrays With Sum Equals Target/cpp_1546/Solution1.h | /**
* @author ooooo
* @date 2021/3/9 11:59
*/
#ifndef CPP_1546__SOLUTION1_H_
#define CPP_1546__SOLUTION1_H_
#include <iostream>
#include <vector>
using namespace std;
// timeout
class Solution {
public:
int maxNonOverlapping(vector<int> &nums, int target) {
int n = nums.size();
vector<int> preSum(n + 1);
for (int i = 0; i < n; ++i) {
preSum[i + 1] = preSum[i] + nums[i];
}
vector<int> dp(n);
for (int i = 0; i < n; ++i) {
if (i > 0) {
dp[i] = dp[i - 1];
}
for (int j = i; j >= 0; --j) {
if (preSum[i + 1] - preSum[j] == target) {
dp[i] = max(dp[i], (j > 0 ? dp[j - 1] : 0) + 1);
}
}
}
return dp[n - 1];
}
};
#endif //CPP_1546__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0160-Intersection-of-Two-Linked-Lists/cpp_0160/Solution2.h | //
// Created by ooooo on 2020/1/23.
//
#ifndef CPP_0160__SOLUTION2_H_
#define CPP_0160__SOLUTION2_H_
#include "ListNode.h"
#include <unordered_set>
/**
* 双指针 (循环走A-B)
*/
class Solution {
public:
ListNode *getIntersectionNode(ListNode *headA, ListNode *headB) {
ListNode *pA = headA, *pB = headB;
while (pA != pB) {
pA = pA ? pA->next : headB;
pB = pB ? pB->next : headA;
}
return pA;
}
};
#endif //CPP_0160__SOLUTION2_H_
|
ooooo-youwillsee/leetcode | 0264-Ugly Number II/cpp_0264/Solution2.h | <filename>0264-Ugly Number II/cpp_0264/Solution2.h
/**
* @author ooooo
* @date 2021/4/11 15:17
*/
#ifndef CPP_0264__SOLUTION2_H_
#define CPP_0264__SOLUTION2_H_
#include <iostream>
#include <vector>
using namespace std;
class Solution {
public:
using ll = long long;
int nthUglyNumber(int n) {
vector<ll> dp(n, 1);
int p2 = 0, p3 = 0, p5 = 0;
for (int i = 0; i < n - 1; i++) {
ll a = dp[p2] * 2, b = dp[p3] * 3, c = dp[p5] * 5;
ll v = min(a, min(b, c));
dp[i + 1] = v;
if (v == a) {
p2++;
}
if (v == b) {
p3++;
}
if (v == c) {
p5++;
}
}
return dp[n - 1];
}
};
#endif //CPP_0264__SOLUTION2_H_
|
ooooo-youwillsee/leetcode | 0001-Two-Sum/cpp_0001/Solution1.h | #include <vector>
#include <iostream>
using namespace std;
/**
* 暴力破解法
*/
class Solution1 {
public:
static vector<int> twoSum(vector<int> &nums, int target) {
vector<int> result;
for (int i = 0; i < nums.size(); ++i) {
for (int j = 1; j < nums.size(); ++j) {
if (nums[j] + nums[i] == target) {
result.push_back(i);
result.push_back(j);
break;
}
}
}
return result;
}
}; |
ooooo-youwillsee/leetcode | 0403-Frog Jump/cpp_0403/Solution1.h | <reponame>ooooo-youwillsee/leetcode
/**
* @author ooooo
* @date 2021/4/30 19:57
*/
#ifndef CPP_0403__SOLUTION1_H_
#define CPP_0403__SOLUTION1_H_
#include <iostream>
#include <vector>
#include <unordered_map>
using namespace std;
class Solution {
public:
/*
* i 表示第几个位置， step 表示上一步的步数
*/
bool dfs(int i, int step) {
if (memo.find(i) != memo.end()) {
if (memo[i].find(step) != memo[i].end()) {
return memo[i][step];
}
}
if (i == can.size()) return true;
if (i > can.size()) return false;
bool pass = false;
if (i + step - 1 > i && can[i+step-1]) {
pass = dfs(i + step - 1, step - 1);
}
if (i + step > i && can[i+step]) {
pass = pass || dfs(i + step, step);
}
if (i + step + 1 > i && can[i+step+1]) {
pass = pass || dfs(i + step + 1, step + 1);
}
return memo[i][step] = pass;
}
vector<bool> can;
unordered_map<int, unordered_map<int, bool>> memo;
bool canCross(vector<int>& stones) {
can.assign(stones[stones.size() - 1], false);
for (auto i: stones){
can[i] = true;
}
if (!can[1]) return false;
return dfs(1, 1);
}
};
#endif //CPP_0403__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 1269-Number of Ways to Stay in the Same Place After Some Steps/cpp_1269/Solution2.h | <gh_stars>10-100
/**
* @author ooooo
* @date 2021/5/14 21:06
*/
#ifndef CPP_1269__SOLUTION2_H_
#define CPP_1269__SOLUTION2_H_
#include <iostream>
#include <vector>
using namespace std;
class Solution {
public:
const int mod = 1e9 + 7;
int numWays(int steps, int arrLen) {
int maxJ = min(arrLen, steps);
vector<vector<long long>> dp(steps + 1, vector<long long>(maxJ, 0));
dp[0][0] = 1;
for (int i = 1; i <= steps; i++) {
for (int j = 0; j < maxJ; j++) {
dp[i][j] = dp[i - 1][j];
if (j - 1 >= 0) {
dp[i][j] = (dp[i][j] + dp[i - 1][j - 1]) % mod;
}
if (j + 1 < maxJ) {
dp[i][j] = (dp[i][j] + dp[i - 1][j + 1]) % mod;
}
}
}
return dp[steps][0];
}
};
#endif //CPP_1269__SOLUTION2_H_
|
ooooo-youwillsee/leetcode | 0554-Brick Wall/cpp_0554/Solution1.h | <gh_stars>10-100
/**
* @author ooooo
* @date 2021/5/2 08:14
*/
#ifndef CPP_0554__SOLUTION1_H_
#define CPP_0554__SOLUTION1_H_
#include <iostream>
#include <vector>
#include <unordered_map>
using namespace std;
class Solution {
public:
int leastBricks(vector<vector<int>> &wall) {
unordered_map<int, int> m;
for (int i = 0; i < wall.size(); i++) {
vector<int> w = wall[i];
int preSum = 0;
for (int j = 0; j < w.size() - 1; j++) {
preSum += w[j];
m[preSum]++;
}
}
int maxCol = 0;
for (auto &e: m) {
maxCol = max(maxCol, e.second);
}
return wall.size() - maxCol;
}
};
#endif //CPP_0554__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0279-Perfect-Squares/cpp_0279/Solution3.h | <filename>0279-Perfect-Squares/cpp_0279/Solution3.h
//
// Created by ooooo on 2020/2/23.
//
#ifndef CPP_0279__SOLUTION3_H_
#define CPP_0279__SOLUTION3_H_
#include <iostream>
#include <vector>
#include <math.h>
using namespace std;
/**
* dp[i] = min(dp[i], dp[i - j*j] + 1 )
*/
class Solution {
public:
int numSquares(int n) {
vector<int> dp(n + 1, 0);
for (int i = 1; i <= n; ++i) {
dp[i] = i; // 最多就是所有的 1 相加
for (int j = 1; i - j * j >= 0; ++j) {
dp[i] = min(dp[i], dp[i - j * j] + 1);
}
}
return dp[n];
}
};
#endif //CPP_0279__SOLUTION3_H_
|
ooooo-youwillsee/leetcode | 0307-Range-Sum-Query-Mutable/cpp_0307/Solution1.h | <reponame>ooooo-youwillsee/leetcode<filename>0307-Range-Sum-Query-Mutable/cpp_0307/Solution1.h
//
// Created by ooooo on 2020/2/2.
//
#ifndef CPP_0307__SOLUTION1_H_
#define CPP_0307__SOLUTION1_H_
#include <iostream>
#include <vector>
using namespace std;
class NumArray {
private:
template<typename T>
struct SegmentTree {
vector<T> tree, data;
SegmentTree(vector<T> data) : data(data.size()), tree(data.size() * 4) {
for (int i = 0; i < data.size(); ++i) {
this->data[i] = data[i];
}
if (!data.empty()) {
buildSegmentTree(0, 0, data.size() - 1);
}
}
void buildSegmentTree(int treeIndex, int left, int right) {
if (left == right) {
this->tree[treeIndex] = this->data[left];
return;
}
int mid = left + (right - left) / 2;
buildSegmentTree(leftChild(treeIndex), left, mid);
buildSegmentTree(rightChild(treeIndex), mid + 1, right);
tree[treeIndex] = merge(tree[leftChild(treeIndex)], tree[rightChild(treeIndex)]);
}
T query(int queryL, int queryR) {
return query(0, 0, data.size() - 1, queryL, queryR);
}
T query(int treeIndex, int left, int right, int queryL, int queryR) {
if (queryL == left && queryR == right) {
return tree[treeIndex];
}
int mid = left + (right - left) / 2;
if (queryL > mid) {
return query(rightChild(treeIndex), mid + 1, right, queryL, queryR);
} else if (queryR <= mid) {
return query(leftChild(treeIndex), left, mid, queryL, queryR);
}
T leftResult = query(leftChild(treeIndex), left, mid, queryL, mid);
T rightResult = query(rightChild(treeIndex), mid + 1, right, mid + 1, queryR);
return merge(leftResult, rightResult);
}
void set(int i, T v) {
this->data[i] = v;
set(0, 0, data.size() - 1, i);
}
void set(int treeIndex, int left, int right, int targetIndex) {
if (left == right) {
tree[treeIndex] = data[left];
return;
}
int mid = left + (right - left) / 2;
if (targetIndex > mid) {
set(rightChild(treeIndex), mid + 1, right, targetIndex);
} else if (targetIndex <= mid) {
set(leftChild(treeIndex), left, mid, targetIndex);
}
tree[treeIndex] = merge(tree[leftChild(treeIndex)], tree[rightChild(treeIndex)]);
}
int leftChild(int i) {
return 2 * i + 1;
}
int rightChild(int i) {
return 2 * i + 2;
}
T merge(T a, T b) {
return a + b;
}
};
SegmentTree<int> segmentTree;
int size;
public:
NumArray(vector<int> &nums) : segmentTree(nums) {
}
void update(int i, int val) {
segmentTree.set(i, val);
}
int sumRange(int i, int j) {
return segmentTree.query(i, j);
}
};
#endif //CPP_0307__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 1122-Relative-Sort-Array/cpp_1122/Solution1.h | <reponame>ooooo-youwillsee/leetcode
/**
* @author ooooo
* @date 2020/11/14 20:22
*/
#ifndef CPP_1122__SOLUTION1_H_
#define CPP_1122__SOLUTION1_H_
#include <iostream>
#include <vector>
#include <unordered_map>
using namespace std;
class Solution {
public:
vector<int> relativeSortArray(vector<int> &arr1, vector<int> &arr2) {
unordered_map<int, int> indexes_map;
for (int i = 0; i < arr2.size(); ++i) {
indexes_map[arr2[i]] = i;
}
vector<int> ans, other;
for (auto &item: arr1) {
if (indexes_map.find(item) != indexes_map.end()) {
ans.push_back(item);
} else {
other.push_back(item);
}
}
sort(ans.begin(), ans.end(), [&](int x, int y) {
return indexes_map[x] < indexes_map[y];
});
sort(other.begin(), other.end());
ans.insert(ans.end(), other.begin(), other.end());
return ans;
}
};
#endif //CPP_1122__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 1319-Number of Operations to Make Network Connected/cpp_1319/Solution1.h | /**
* @author ooooo
* @date 2021/1/23 12:45
*/
#ifndef CPP_1319__SOLUTION1_H_
#define CPP_1319__SOLUTION1_H_
#include <iostream>
#include <vector>
using namespace std;
class Solution {
public:
struct UF {
int n;
vector<int> p;
UF(int n) : n(n), p(n) {
for (int i = 0; i < n; ++i) {
p[i] = i;
}
}
int find(int i) {
if (p[i] == i) return i;
return p[i] = find(p[i]);
}
bool connected(int i, int j) {
int pi = find(i), pj = find(j);
if (pi == pj) return true;
return false;
}
void connect(int i, int j) {
int pi = find(i), pj = find(j);
if (pi == pj) return;
p[pi] = pj;
n--;
}
};
int makeConnected(int n, vector<vector<int>> &connections) {
UF uf(n);
int idle = 0;
for (int i = 0; i < connections.size(); ++i) {
if (uf.connected(connections[i][0], connections[i][1])) {
idle++;
} else {
uf.connect(connections[i][0], connections[i][1]);
}
}
int ans = 0;
for (int i = 0; i < n; ++i) {
if (!uf.connected(0, i)) {
ans++;
uf.connect(0, i);
if (ans > idle) return -1;
}
}
return ans;
}
};
#endif //CPP_1319__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0167-Two-Sum-II-Input-array-is-sorted/cpp_0167/Solution1.h | //
// Created by ooooo on 2020/1/6.
//
#ifndef CPP_0167_SOLUTION1_H
#define CPP_0167_SOLUTION1_H
#include <iostream>
#include <vector>
using namespace std;
class Solution {
public:
vector<int> twoSum(vector<int> &numbers, int target) {
for (int i = 0, j = numbers.size() - 1; i < j;) {
int sum = numbers[i] + numbers[j];
if (sum == target) return {i + 1, j + 1};
else if (sum < target) i++;
else j--;
}
return {};
}
};
#endif //CPP_0167_SOLUTION1_H
|
ooooo-youwillsee/leetcode | 0078-Subsets/cpp_0078/Solution3.h | /**
* @author ooooo
* @date 2020/9/20 12:14
*/
#ifndef CPP_0078__SOLUTION3_H_
#define CPP_0078__SOLUTION3_H_
#include <iostream>
#include <vector>
using namespace std;
class Solution {
public:
vector<vector<int>> ans;
vector<int> nums;
void dfs(vector<int> &num, int i) {
ans.push_back(num);
if (i == nums.size()) return;
for (int j = i; j < nums.size(); ++j) {
num.push_back(nums[j]);
dfs(num, j + 1);
num.pop_back();
}
}
vector<vector<int>> subsets(vector<int> &nums) {
sort(nums.begin(), nums.end());
this->nums = nums;
vector<int> num;
dfs(num, 0);
return ans;
}
};
#endif //CPP_0078__SOLUTION3_H_
|
ooooo-youwillsee/leetcode | 1793-Maximum Score of a Good Subarray/cpp_1793/Solution1.h | /**
* @author ooooo
* @date 2021/3/28 12:14
*/
#ifndef CPP_1793__SOLUTION1_H_
#define CPP_1793__SOLUTION1_H_
#include <iostream>
#include <vector>
#include <unordered_map>
#include <unordered_set>
#include <set>
#include <stack>
#include <numeric>
#include <queue>
using namespace std;
class Solution {
public:
int maximumScore(vector<int> &nums, int k) {
int n = nums.size();
int ans = 0;
int i = k, j = k;
int minValue = nums[k];
while (i >= 0 && j < n) {
ans = max(ans, minValue * (j - i + 1));
if (i - 1 >= 0 && j + 1 < n) {
if (nums[i - 1] <= nums[j + 1]) {
minValue = min(minValue, nums[j + 1]);
j++;
} else {
minValue = min(minValue, nums[i - 1]);
i--;
}
} else {
break;
}
}
int p = i, q = j;
while (i >= 0) {
minValue = min(minValue, nums[i]);
ans = max(ans, minValue * (q - i + 1));
i--;
}
while (j < n) {
minValue = min(minValue, nums[j]);
ans = max(ans, minValue * (j - p + 1));
j++;
}
return ans;
}
};
#endif //CPP_1793__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0083-Remove-Duplicates-from-Sorted-List/cpp_0083/Solution2.h | <gh_stars>10-100
//
// Created by ooooo on 2020/1/23.
//
#ifndef CPP_0083__SOLUTION2_H_
#define CPP_0083__SOLUTION2_H_
#include "ListNode.h"
/**
* recursion
*/
class Solution {
public:
ListNode *deleteDuplicates(ListNode *head) {
if (!head) return nullptr;
head->next = deleteDuplicates(head->next);
return head->next && head->next->val == head->val ? head->next : head;
}
};
#endif //CPP_0083__SOLUTION2_H_
|
ooooo-youwillsee/leetcode | lcof_054/cpp_054/Solution1.h | //
// Created by ooooo on 2020/4/11.
//
#ifndef CPP_054__SOLUTION1_H_
#define CPP_054__SOLUTION1_H_
#include "TreeNode.h"
#include <vector>
class Solution {
public:
void dfs(TreeNode *node) {
if (!node) return;
dfs(node->left);
nums.push_back(node->val);
dfs(node->right);
}
vector<int> nums;
int kthLargest(TreeNode *root, int k) {
dfs(root);
return nums[nums.size() - k];
}
};
#endif //CPP_054__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0169-Majority-Element/cpp_0169/Solution1.h | //
// Created by ooooo on 2019/11/4.
//
#ifndef CPP_0169_SOLUTION1_H
#define CPP_0169_SOLUTION1_H
#include <vector>
#include <iostream>
#include <map>
using namespace std;
class Solution {
public:
int majorityElement(vector<int> &nums) {
map<int, int> m;
int size = nums.size();
for (auto i: nums) {
map<int, int>::iterator it = m.find(i);
if (it == m.end()) {
m[i] = 1;
} else {
m[i] = it->second + 1;
}
if (m[i] > size / 2) {
return i;
}
}
return 0;
}
};
#endif //CPP_0169_SOLUTION1_H
|
ooooo-youwillsee/leetcode | 1108-Defanging-an-IP-Address/cpp_1108/Solution1.h | <reponame>ooooo-youwillsee/leetcode<filename>1108-Defanging-an-IP-Address/cpp_1108/Solution1.h
//
// Created by ooooo on 2020/2/2.
//
#ifndef CPP_1108__SOLUTION1_H_
#define CPP_1108__SOLUTION1_H_
#include <iostream>
#include <sstream>
using namespace std;
class Solution {
public:
string defangIPaddr(string address) {
string target = "[.]";
stringstream ss;
for (auto &c: address) {
if (c == '.') {
ss << target;
} else {
ss << c;
}
}
return ss.str();
}
};
#endif //CPP_1108__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0086-Partition List/cpp_0086/Solution1.h | /**
* @author ooooo
* @date 2021/1/4 16:16
*/
#ifndef CPP_0086__SOLUTION1_H_
#define CPP_0086__SOLUTION1_H_
#include "ListNode.h"
class Solution {
public:
ListNode *partition(ListNode *head, int x) {
ListNode *dummyHead = new ListNode(-1);
dummyHead->next = head;
ListNode *cur = dummyHead;
while (cur && cur->next) {
if (cur->next->val >= x) {
break;
}
cur = cur->next;
}
ListNode *prev = cur;
while (cur && cur->next) {
if (cur->next->val < x) {
auto prev_next = prev->next;
auto cur_next = cur->next->next;
prev->next = cur->next;
prev->next->next = prev_next;
cur->next = cur_next;
prev = prev->next;
continue;
}
cur = cur->next;
}
return dummyHead->next;
}
};
#endif //CPP_0086__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0783-Minimum-Distance-Between-BST-Nodes/cpp_0783/Solution1.h | <reponame>ooooo-youwillsee/leetcode
//
// Created by ooooo on 2020/1/5.
//
#ifndef CPP_0783_SOLUTION1_H
#define CPP_0783_SOLUTION1_H
#include "TreeNode.h"
#include <vector>
class Solution {
public:
void dfs(TreeNode *node, vector<int> &vec) {
if (!node) return;
dfs(node->left, vec);
vec.push_back(node->val);
dfs(node->right, vec);
}
int minDiffInBST(TreeNode *root) {
if (!root) return 0;
vector<int> vec;
dfs(root, vec);
int min = INT_MAX;
for (int i = 0; i < vec.size() - 1; ++i) {
min = std::min(min, vec[i + 1] - vec[i]);
}
return min;
}
};
#endif //CPP_0783_SOLUTION1_H
|
ooooo-youwillsee/leetcode | 0315-Count of Smaller Numbers After Self/cpp_0315/Solution2.h | /**
* @author ooooo
* @date 2020/11/27 13:54
*/
#ifndef CPP_0315__SOLUTION2_H_
#define CPP_0315__SOLUTION2_H_
#include <iostream>
#include <vector>
using namespace std;
class Solution {
public:
vector<int> nums, tmp, indexes, ans, tmp_indexes;
void merge(int l, int mid, int r) {
copy(nums.begin() + l, nums.begin() + r + 1, tmp.begin() + l);
copy(indexes.begin() + l, indexes.begin() + r + 1, tmp_indexes.begin() + l);
int i = l, j = mid + 1;
int k = l;
while (i <= mid && j <= r) {
if (tmp[i] <= tmp[j]) {
nums[k] = tmp[i];
indexes[k] = tmp_indexes[i];
// 经典！！！
ans[tmp_indexes[i]] += (j - mid - 1);
i++;
} else {
//for (int p = i; p <= mid; ++p) {
// ans[tmp_indexes[p]]++;
//}
nums[k] = tmp[j];
indexes[k] = tmp_indexes[j];
j++;
}
k++;
}
while (i <= mid) {
nums[k] = tmp[i];
indexes[k] = tmp_indexes[i];
ans[tmp_indexes[i]] += (j - mid - 1);
i++;
k++;
}
while (j <= r) {
nums[k] = tmp[j];
indexes[k] = tmp_indexes[j];
j++;
k++;
}
}
void mergeSort(int l, int r) {
if (l >= r) return;
int mid = l + (r - l) / 2;
mergeSort(l, mid);
mergeSort(mid + 1, r);
merge(l, mid, r);
}
vector<int> countSmaller(vector<int> &nums) {
int n = nums.size();
this->nums = nums;
ans.assign(n, 0);
tmp.assign(n, 0);
indexes.assign(n, 0);
tmp_indexes.assign(n, 0);
for (int i = 0; i < n; ++i) {
indexes[i] = i;
}
mergeSort(0, nums.size() - 1);
//for (auto &num : this->nums) {
// cout << num << " ";
//}
//cout << endl;
return ans;
}
};
#endif //CPP_0315__SOLUTION2_H_
|
ooooo-youwillsee/leetcode | 0409-Longest-Palindrome/cpp_0409/Solution1.h | <filename>0409-Longest-Palindrome/cpp_0409/Solution1.h
//
// Created by ooooo on 2020/1/11.
//
#ifndef CPP_0409__SOLUTION1_H_
#define CPP_0409__SOLUTION1_H_
#include <iostream>
#include <unordered_map>
using namespace std;
class Solution {
public:
int longestPalindrome(string s) {
if (s.empty()) return 0;
unordered_map<char, int> m;
for (auto &c: s) {
m[c]++;
}
int i = 0, j = 0;
for (auto &entry: m) {
j += entry.second / 2;
if (entry.second % 2 == 1) {
// 有多余的置为1
i = 1;
}
}
return i + j * 2;
}
};
#endif //CPP_0409__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0300-Longest-Increasing-Subsequence/cpp_0300/Solution1.h | //
// Created by ooooo on 2020/2/24.
//
#ifndef CPP_0300__SOLUTION1_H_
#define CPP_0300__SOLUTION1_H_
#include <iostream>
#include <vector>
using namespace std;
/**
* dp[i] = num[j] < num[i] ==> max( dp[i] , dp[j] + 1 )
*/
class Solution {
public:
int lengthOfLIS(vector<int> &nums) {
int n = nums.size(), ans = 0;
if (n <= 1) return n;
vector<int> dp(n, 1);
for (int i = 1; i < n; ++i) {
for (int j = 0; j < i; ++j) {
if (nums[j] < nums[i]) {
dp[i] = max(dp[i], dp[j] + 1);
}
ans = max(ans, dp[i]);
}
}
return ans;
}
};
#endif //CPP_0300__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0119-Pascals-Triangle-II/cpp_0119/Solution1.h | <reponame>ooooo-youwillsee/leetcode
//
// Created by ooooo on 2020/1/6.
//
#ifndef CPP_0119_SOLUTION1_H
#define CPP_0119_SOLUTION1_H
#include <iostream>
#include <vector>
using namespace std;
/**
* 动态规划
*/
class Solution {
public:
vector<int> getRow2(int rowIndex) {
if (rowIndex == 0) return {1};
vector<int> ans(rowIndex + 1, 1);
for (int i = 1; i <= rowIndex; ++i) {
for (int rightIndex = i - 1; rightIndex > 0; --rightIndex) {
ans[rightIndex] += ans[rightIndex - 1];
}
}
return ans;
}
vector<int> getRow(int rowIndex) {
vector<int> ans;
for (int i = 0; i <= rowIndex; ++i) {
ans.push_back(1);
for (int rightIndex = i - 1; rightIndex > 0; --rightIndex) {
ans[rightIndex] += ans[rightIndex - 1];
}
}
return ans;
}
};
#endif //CPP_0119_SOLUTION1_H
|
ooooo-youwillsee/leetcode | 1237-Find-Positive-Integer-Solution-for-a-Given-Equation/cpp_1237/CustomFunction.h | <reponame>ooooo-youwillsee/leetcode
//
// Created by ooooo on 2020/1/22.
//
#ifndef CPP_1237__CUSTOMFUNCTION_H_
#define CPP_1237__CUSTOMFUNCTION_H_
#include <iostream>
#include <vector>
using namespace std;
class CustomFunction {
public:
// Returns f(x, y) for any given positive integers x and y.
// Note that f(x, y) is increasing with respect to both x and y.
// i.e. f(x, y) < f(x + 1, y), f(x, y) < f(x, y + 1)
int f(int x, int y) {
return x + y;
}
};
#endif //CPP_1237__CUSTOMFUNCTION_H_
|
ooooo-youwillsee/leetcode | 0034-Search-for-a-Range/cpp_0034/Solution2.h | <filename>0034-Search-for-a-Range/cpp_0034/Solution2.h
//
// Created by ooooo on 2020/2/9.
//
#ifndef CPP_0034__SOLUTION2_H_
#define CPP_0034__SOLUTION2_H_
#include <iostream>
#include <vector>
using namespace std;
/**
* 二分法 (找到左边界和右边界)
*/
class Solution {
public:
int findBound(vector<int> nums, int target, bool isLeft) {
if (nums.empty()) return -1;
int left = 0, right = nums.size() - 1;
while (left < right) {
// isLeft ? 0 : 1 --> 默认向左偏
int mid = left + (right - left + (isLeft ? 0 : 1)) / 2;
if (nums[mid] > target) {
right = mid - 1;
} else if (nums[mid] < target) {
left = mid + 1;
} else {
if (isLeft) {
right = mid;
} else {
left = mid;
}
}
}
return nums[left] == target ? left : -1;
}
vector<int> searchRange(vector<int> &nums, int target) {
if (nums.empty()) return {-1, -1};
int leftIndex = findBound(nums, target, true);
if (leftIndex == -1) return {-1, -1};
return {leftIndex, findBound(nums, target, false)};
}
};
#endif //CPP_0034__SOLUTION2_H_
|
ooooo-youwillsee/leetcode | 1813-Sentence Similarity III/cpp_1813/Solution1.h | /**
* @author ooooo
* @date 2021/4/11 15:31
*/
#ifndef CPP_1813__SOLUTION1_H_
#define CPP_1813__SOLUTION1_H_
#include <iostream>
#include <vector>
#include <sstream>
#include <queue>
using namespace std;
class Solution {
public:
bool areSentencesSimilar(string sentence1, string sentence2) {
auto split = [](const string &s) {
istringstream in(s);
string w;
deque<string> words;
while (in >> w) {
words.push_back(w);
}
return words;
};
if (sentence1.size() < sentence2.size()) swap(sentence1, sentence2);
deque<string> word1 = split(sentence1), word2 = split(sentence2);
while (!word2.empty() && word1.front() == word2.front()) {
word1.pop_front();
word2.pop_front();
}
while (!word2.empty() && word1.back() == word2.back()) {
word1.pop_back();
word2.pop_back();
}
return word2.empty();
}
};
#endif //CPP_1813__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0014-Longest-Common-Prefix/cpp_0014/Solution1.h | <reponame>ooooo-youwillsee/leetcode
//
// Created by ooooo on 2020/1/24.
//
#ifndef CPP_0014__SOLUTION1_H_
#define CPP_0014__SOLUTION1_H_
#include <iostream>
#include <vector>
using namespace std;
class Solution {
public:
string check(string s1, string s2) {
int len = s1.size() < s2.size() ? s1.size() : s2.size();
string ans = "";
for (int i = 0; i < len; ++i) {
if (s1[i] != s2[i]) return ans;
ans += string(1, s1[i]);
}
return ans;
}
string longestCommonPrefix(vector<string> &strs) {
if (strs.empty()) return "";
string ans = strs[0];
for (int i = 1; i < strs.size(); ++i) {
ans = check(ans, strs[i]);
}
return ans;
}
};
#endif //CPP_0014__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0395-Longest Substring with At Least K Repeating Characters/cpp_0395/Solution2.h | /**
* @author ooooo
* @date 2021/2/27 11:48
*/
#ifndef CPP_0395__SOLUTION2_H_
#define CPP_0395__SOLUTION2_H_
#include <vector>
#include <iostream>
#include <unordered_map>
using namespace std;
// 分治法
class Solution {
public:
int dfs(string &s, int l, int r, int k) {
if (l > r) return 0;
int n = r + 1;
vector<int> m(26, 0);
for (int i = l; i < n; ++i) {
m[s[i] - 'a']++;
}
char split = '0';
for (int i = 0; i < 26; ++i) {
if (m[i] > 0 && m[i] < k) {
// 这个字符没有k个，以它为分界线
split = i + 'a';
break;
}
}
if (split == '0') {
return r - l + 1;
}
int ans = 0;
int i = l;
while (i < n) {
while (i < n && s[i] == split) {
i++;
}
if (i >= n) {
return 0;
}
int j = i;
while (j < n && s[j] != split) {
j++;
}
ans = max(ans, dfs(s, i, j - 1, k));
i = j;
}
return ans;
}
int longestSubstring(string s, int k) {
return dfs(s, 0, s.size() - 1, k);
}
};
#endif //CPP_0395__SOLUTION2_H_
|
ooooo-youwillsee/leetcode | 1806-Minimum Number of Operations to Reinitialize a Permutation/cpp_1806/Solution1.h | <filename>1806-Minimum Number of Operations to Reinitialize a Permutation/cpp_1806/Solution1.h
/**
* @author ooooo
* @date 2021/4/4 08:30
*/
#ifndef CPP_1806__SOLUTION1_H_
#define CPP_1806__SOLUTION1_H_
#include <iostream>
#include <vector>
#include <unordered_map>
#include <unordered_set>
#include <set>
#include <stack>
#include <numeric>
#include <queue>
using namespace std;
class Solution {
public:
int reinitializePermutation(int n) {
int ans = 0;
for (int i = 0; i < n; ++i) {
int cnt = 0;
int cur = i, next = i;
do {
if (next % 2 == 0) {
next = next / 2;
} else {
next = n / 2 + (next - 1) / 2;
}
cnt++;
} while (next != cur);
ans = max(ans, cnt);
}
return ans;
}
};
#endif //CPP_1806__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 1684-Count the Number of Consistent Strings/cpp_1684/Solution1.h | /**
* @author ooooo
* @date 2020/12/20 13:03
*/
#ifndef CPP_1684__SOLUTION1_H_
#define CPP_1684__SOLUTION1_H_
#include <iostream>
#include <vector>
#include <unordered_set>
using namespace std;
class Solution {
public:
int countConsistentStrings(string allowed, vector<string> &words) {
int ans = 0;
unordered_set<char> set(allowed.begin(), allowed.end());
for (auto &word: words) {
bool flag = true;
for (auto &c: word) {
if (!set.count(c)) {
flag = false;
break;
}
}
if (flag) {
ans++;
}
}
return ans;
}
};
#endif //CPP_1684__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | lcof_040/cpp_040/Solution2.h | //
// Created by ooooo on 2020/3/25.
//
#ifndef CPP_040__SOLUTION2_H_
#define CPP_040__SOLUTION2_H_
#include <iostream>
#include <vector>
using namespace std;
class Solution {
public:
vector<int> getLeastNumbers(vector<int> &arr, int k) {
if (k == 0) return {};
sort(arr.begin(), arr.end());
return vector<int>(arr.begin(), arr.begin() + k);
}
};
#endif //CPP_040__SOLUTION2_H_
|
ooooo-youwillsee/leetcode | 1726-Tuple with Same Product/cpp_1726/Solution1.h | /**
* @author ooooo
* @date 2021/1/24 17:07
*/
#ifndef CPP_1726__SOLUTION1_H_
#define CPP_1726__SOLUTION1_H_
#include <iostream>
#include <vector>
#include <unordered_map>
#include <queue>
#include <unordered_set>
#include <set>
using namespace std;
class Solution {
public:
int tupleSameProduct(vector<int> &nums) {
int ans = 0;
int n = nums.size();
unordered_map<int, int> m;
for (int i = 0; i < n; ++i) {
for (int j = i + 1; j < n; ++j) {
int x = nums[i] * nums[j];
ans += m[x] * 4 * 2;
m[x]++;
}
}
return ans;
}
};
#endif //CPP_1726__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0477-Total Hamming Distance/cpp_0477/Solution1.h | /**
* @author ooooo
* @date 2021/5/28 11:13
*/
#ifndef CPP_0477__SOLUTION1_H_
#define CPP_0477__SOLUTION1_H_
#include <iostream>
#include <vector>
using namespace std;
class Solution {
public:
int totalHammingDistance(vector<int> &nums) {
int ans = 0;
int n = nums.size();
for (int i = 0; i < 32; i++) {
int cnt_1 = 0;
for (int j = 0; j < n; j++) {
cnt_1 += (nums[j] >> i & 1);
}
ans += (n - cnt_1) * cnt_1;
}
return ans;
}
};
#endif //CPP_0477__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0219-Contains-Duplicate-II/cpp_0219/Solution1.h | //
// Created by ooooo on 2020/1/6.
//
#ifndef CPP_0219_SOLUTION1_H
#define CPP_0219_SOLUTION1_H
#include <iostream>
#include <vector>
#include <unordered_map>
using namespace std;
/**
* 存在 索引差为k 就返回true
*/
class Solution {
public:
bool containsNearbyDuplicate(vector<int> &nums, int k) {
unordered_map<int, int> m;
for (int i = 0, len = nums.size(); i < len; ++i) {
if (m.count(nums[i]) && i - m[nums[i]] <= k) {
return true;
}
m[nums[i]] = i;
}
return false;
}
};
#endif //CPP_0219_SOLUTION1_H
|
ooooo-youwillsee/leetcode | 0206-Reverse-Linked-List/cpp_0206/Solution2.h | <reponame>ooooo-youwillsee/leetcode
//
// Created by ooooo on 2019/10/29.
//
#ifndef CPP_0206_SOLUTION2_H
#define CPP_0206_SOLUTION2_H
#include <iostream>
#include "ListNode.h"
using namespace std;
class Solution2 {
public:
ListNode *reverseList(ListNode *head) {
if (head == NULL || head->next == NULL) return head;
ListNode *pNode = reverseList(head->next);
head->next->next = head;
head->next = NULL;
return pNode;
}
};
#endif //CPP_0206_SOLUTION2_H
|
ooooo-youwillsee/leetcode | 0122-Best-Time-to-Buy-and-Sell-Stock-II/cpp_0122/Solution1.h | <filename>0122-Best-Time-to-Buy-and-Sell-Stock-II/cpp_0122/Solution1.h<gh_stars>10-100
//
// Created by ooooo on 2019/11/4.
//
#ifndef CPP_0122_SOLUTION1_H
#define CPP_0122_SOLUTION1_H
#include <iostream>
#include <vector>
using namespace std;
/**
* 贪心算法
*/
class Solution {
public:
int maxProfit(vector<int> &prices) {
int res = 0;
for (int i = 0; !prices.empty() && i < prices.size() - 1; ++i) {
if (prices[i + 1] > prices[i]) {
res += prices[i + 1] - prices[i];
}
}
return res;
}
};
#endif //CPP_0122_SOLUTION1_H
|
ooooo-youwillsee/leetcode | lcof_039/cpp_039/Solution1.h | <reponame>ooooo-youwillsee/leetcode
//
// Created by ooooo on 2020/3/24.
//
#ifndef CPP_039__SOLUTION1_H_
#define CPP_039__SOLUTION1_H_
#include <iostream>
#include <vector>
#include <unordered_map>
using namespace std;
/**
* hash
*/
class Solution {
public:
int majorityElement(vector<int> &nums) {
unordered_map<int, int> num_map;
int n = nums.size() / 2;
for (auto &num: nums) {
num_map[num]++;
if (num_map[num] > n) return num;
}
return -1;
}
};
#endif //CPP_039__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0347-Top-K-Frequent-Elements/cpp_0347/Solution2.h | <filename>0347-Top-K-Frequent-Elements/cpp_0347/Solution2.h<gh_stars>10-100
/**
* @author ooooo
* @date 2020/9/7 11:08
*/
#ifndef CPP_0347__SOLUTION2_H_
#define CPP_0347__SOLUTION2_H_
#include <vector>
#include <queue>
#include <map>
#include <iostream>
using namespace std;
class Solution {
public:
template <typename T>
struct comp{
bool operator()(const T &p1, const T &p2) const {
return p2.second > p1.second;
}
};
vector<int> topKFrequent(vector<int> &nums, int k) {
map<int, int> m;
for (auto num : nums) m[num]++;
priority_queue<pair<int, int>, vector<pair<int, int>>, comp<pair<int,int>>> q;
for (auto[k, v]: m) {
q.push({k, v});
}
vector<int> ans;
while (k > 0) {
ans.push_back(q.top().first);
q.pop();
k--;
}
return ans;
}
};
#endif //CPP_0347__SOLUTION2_H_
|
ooooo-youwillsee/leetcode | 0104-Maximum-Depth-of-Binary-Tree/cpp_0104/Solution1.h | //
// Created by ooooo on 2019/11/4.
//
#ifndef CPP_0104_SOLUTION1_H
#define CPP_0104_SOLUTION1_H
#include "TreeNode.h"
using namespace std;
class Solution {
private:
int max = 0;
void dfs(int level, TreeNode *node) {
if (!node) return;
if (level > max) max = level;
dfs(level + 1, node->left);
dfs(level + 1, node->right);
}
public:
int maxDepth(TreeNode *root) {
dfs(1, root);
return this->max;
}
};
#endif //CPP_0104_SOLUTION1_H
|
ooooo-youwillsee/leetcode | 0441-Arranging-Coins/cpp_0441/Solution1.h | <reponame>ooooo-youwillsee/leetcode
//
// Created by ooooo on 2020/1/19.
//
#ifndef CPP_0441__SOLUTION1_H_
#define CPP_0441__SOLUTION1_H_
#include <iostream>
using namespace std;
/**
* loop
*/
class Solution {
public:
int arrangeCoins(int n) {
long long sum = 0, i = 0;
while (true) {
if (sum == n) return i;
if (sum > n) return i - 1;
sum += (++i);
}
}
};
#endif //CPP_0441__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0989-Add to Array-Form of Integer/cpp_0989/Solution1.h | /**
* @author ooooo
* @date 2021/1/22 22:45
*/
#ifndef CPP_0989__SOLUTION1_H_
#define CPP_0989__SOLUTION1_H_
#include <iostream>
#include <vector>
using namespace std;
class Solution {
public:
vector<int> addToArrayForm(vector<int> &A, int K) {
vector<int> ans;
int carry = 0, i = A.size() - 1;
while (K) {
int a = carry + K % 10;
if (i >= 0) {
a += A[i];
}
carry = a / 10;
ans.push_back(a % 10);
i--;
K /= 10;
}
while (i >= 0) {
int a = carry + A[i];
carry = a / 10;
ans.push_back(a % 10);
i--;
}
if (carry) {
ans.push_back(carry);
}
reverse(ans.begin(), ans.end());
return ans;
}
};
#endif //CPP_0989__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0701-Insert-into-a-Binary-Search-Tree/cpp_0701/TreeNode.h | <reponame>ooooo-youwillsee/leetcode<filename>0701-Insert-into-a-Binary-Search-Tree/cpp_0701/TreeNode.h
/**
* @author ooooo
* @date 2020/9/30 09:16
*/
#ifndef CPP_0701__TREENODE_H_
#define CPP_0701__TREENODE_H_
#include <iostream>
using namespace std;
struct TreeNode {
int val;
TreeNode *left;
TreeNode *right;
TreeNode() : val(0), left(nullptr), right(nullptr) {}
TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}
};
#endif //CPP_0701__TREENODE_H_
|
ooooo-youwillsee/leetcode | 0053-Maximum-Subarray/cpp_0053/Solution1.h | <reponame>ooooo-youwillsee/leetcode<gh_stars>10-100
//
// Created by ooooo on 2020/2/4.
//
#ifndef CPP_0053__SOLUTION1_H_
#define CPP_0053__SOLUTION1_H_
#include <iostream>
#include <vector>
using namespace std;
/**
* dp[i] 表示数组长度为i的最大连续数组
* dp[i] = nums[i] (dp[i-1] < 0)
* dp[i] = dp[i-1] + nums[i] (dp[i-1] >= 0) 前一个大于0，有增益效果，所有加上
*
*/
class Solution {
public:
int maxSubArray(vector<int> &nums) {
int ans = nums[0];
vector<int> dp(nums.size(), 0);
dp[0] = nums[0];
for (int i = 1; i < nums.size(); ++i) {
if (dp[i - 1] < 0) {
dp[i] = nums[i];
} else {
dp[i] = dp[i - 1] + nums[i];
}
ans = max(ans, dp[i]);
}
return ans;
}
int maxSubArray2(vector<int> &nums) {
int ans = nums[0], sum = 0;
for (auto &num: nums) {
if (sum > 0) {
sum += num;
} else {
sum = num;
}
ans = max(sum, ans);
}
return ans;
}
};
#endif //CPP_0053__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0649-Dota2 Senate/cpp_0649/Solution1.h | <reponame>ooooo-youwillsee/leetcode
/**
* @author ooooo
* @date 2020/12/11 09:11
*/
#ifndef CPP_0649__SOLUTION1_H_
#define CPP_0649__SOLUTION1_H_
#include <iostream>
#include <vector>
#include <queue>
using namespace std;
class Solution {
public:
string predictPartyVictory(string senate) {
queue<int> R, D;
int n = senate.size();
for (int i = 0; i < n; ++i) {
if (senate[i] == 'R') {
R.push(i);
} else {
D.push(i);
}
}
while (!R.empty() && !D.empty()) {
if (R.front() < D.front()) {
R.push(R.front() + n);
} else {
D.push(D.front() + n);
}
D.pop();
R.pop();
}
return D.empty() ? "Radiant" : "Dire";
}
};
#endif //CPP_0649__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 1642-Furthest Building You Can Reach/cpp_1642/Solution1.h | <reponame>ooooo-youwillsee/leetcode
/**
* @author ooooo
* @date 2021/3/6 16:09
*/
#ifndef CPP_1642__SOLUTION1_H_
#define CPP_1642__SOLUTION1_H_
#include <iostream>
#include <queue>
#include <vector>
using namespace std;
// 堆
class Solution {
public:
int furthestBuilding(vector<int> &heights, int bricks, int ladders) {
int n = heights.size();
int i = 0;
priority_queue<int, vector<int>, greater<int>> pq;
int sum = 0;
for (; i < n - 1; ++i) {
int diff = heights[i + 1] - heights[i];
if (diff > 0) {
// 直接用梯子
pq.push(diff);
if (pq.size() > ladders) {
// 改用砖块
sum += pq.top();
pq.pop();
}
if (sum > bricks) {
return i;
}
}
}
return i;
}
};
#endif //CPP_1642__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0024-Swap-Nodes-in-Pairs/cpp_0024/ListNode.h | //
// Created by ooooo on 2019/10/30.
//
#ifndef CPP_0024_LISTNODE_H
#define CPP_0024_LISTNODE_H
#include <iostream>
using namespace std;
struct ListNode {
int val;
ListNode *next;
ListNode(int x) : val(x), next(NULL) {}
};
#endif //CPP_0024_LISTNODE_H
|
ooooo-youwillsee/leetcode | 0303-Range-Sum-Query-Immutable/cpp_0303/Solution2.h | //
// Created by ooooo on 2020/1/29.
//
#ifndef CPP_0303__SOLUTION2_H_
#define CPP_0303__SOLUTION2_H_
#include <iostream>
#include <vector>
/**
* 线段树
*/
using namespace std;
class NumArray {
private:
int *tree;
int *data;
int size;
public:
NumArray(vector<int> &nums) {
data = new int[nums.size()];
for (int i = 0; i < nums.size(); ++i) {
data[i] = nums[i];
}
size = nums.size();
tree = new int[nums.size() * 4];
buildSegmentTree(0, 0, size - 1);
}
void buildSegmentTree(int treeIndex, int left, int right) {
if (left == right) {
tree[treeIndex] = data[left];
return;
}
int mid = left + (right - left) / 2;
buildSegmentTree(leftChild(treeIndex), left, mid);
buildSegmentTree(rightChild(treeIndex), mid + 1, right);
tree[treeIndex] = merge(tree[leftChild(treeIndex)], tree[rightChild(treeIndex)]);
}
int merge(int a, int b) {
return a + b;
}
int leftChild(int i) {
return 2 * i + 1;
}
int rightChild(int i) {
return 2 * i + 2;
}
int sumRange(int i, int j) {
return sumRange(0, 0, size - 1, i, j);
}
int sumRange(int treeIndex, int left, int right, int queryLeft, int queryRight) {
if (queryLeft == left && queryRight == right) {
return tree[treeIndex];
}
int mid = left + (right - left) / 2;
if (queryLeft > mid) {
return sumRange(rightChild(treeIndex), mid + 1, right, queryLeft, queryRight);
} else if (queryRight <= mid) {
return sumRange(leftChild(treeIndex), left, mid, queryLeft, queryRight);
}
int leftValue = sumRange(leftChild(treeIndex), left, mid, queryLeft, mid);
int rightValue = sumRange(rightChild(treeIndex), mid + 1, right, mid + 1, queryRight);
return merge(leftValue, rightValue);
}
};
#endif //CPP_0303__SOLUTION2_H_
|
ooooo-youwillsee/leetcode | 1573-Number of Ways to Split a String/cpp_1573/Solution1.h | /**
* @author ooooo
* @date 2021/3/3 17:21
*/
#ifndef CPP_1573__SOLUTION1_H_
#define CPP_1573__SOLUTION1_H_
#include <iostream>
#include <vector>
using namespace std;
class Solution {
public:
static constexpr int MOD = 1000000007;
int numWays(string s) {
long long n = s.size();
int cnt = 0;
for (auto c : s) {
if (c == '1') {
cnt++;
}
}
if (cnt % 3 != 0) {
return 0;
}
if (cnt == 0) {
return ((n - 2) * (n - 1) / 2) % MOD;
}
int l1 = 0, l2 = 0;
int curCnt = 0;
while (curCnt < cnt / 3) {
if (s[l1] == '1') {
curCnt++;
}
l1++;
}
l2 = l1;
while (s[l2] != '1') l2++;
int r1 = n - 1, r2 = n - 1;
curCnt = 0;
while (curCnt < cnt / 3) {
if (s[r2] == '1') {
curCnt++;
}
r2--;
}
r1 = r2;
while (s[r1] != '1') r1--;
return (long long) (r2 - r1 + 1) * (long long) (l2 - l1 + 1) % MOD;
}
};
#endif //CPP_1573__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 0872-Leaf-Similar-Trees/cpp_0872/Solution1.h | <reponame>ooooo-youwillsee/leetcode<gh_stars>10-100
//
// Created by ooooo on 2020/1/5.
//
#ifndef CPP_0872_SOLUTION1_H
#define CPP_0872_SOLUTION1_H
#include "TreeNode.h"
#include <vector>
class Solution {
public:
void dfs(TreeNode *node, vector<int> &vec) {
if (!node) return;
dfs(node->left, vec);
if (!node->left && !node->right) {
vec.push_back(node->val);
}
dfs(node->right, vec);
}
bool leafSimilar(TreeNode *root1, TreeNode *root2) {
if (!root1 && !root2) return true;
vector<int> vec1, vec2;
dfs(root1, vec1);
dfs(root2, vec2);
return vec1 == vec2;
}
};
#endif //CPP_0872_SOLUTION1_H
|
ooooo-youwillsee/leetcode | lcof_050/cpp_050/Solution1.h | <gh_stars>10-100
//
// Created by ooooo on 2020/4/7.
//
#ifndef CPP_050__SOLUTION1_H_
#define CPP_050__SOLUTION1_H_
#include <iostream>
#include <unordered_map>
using namespace std;
class Solution {
public:
char firstUniqChar(string s) {
unordered_map<char, int> m;
for (auto &c: s) {
m[c]++;
}
for (auto &c:s) {
if (m[c] > 1) continue;
return c;
}
return ' ';
}
};
#endif //CPP_050__SOLUTION1_H_
|
ooooo-youwillsee/leetcode | 1870-Minimum Speed to Arrive on Time/cpp_1870/Solution1.h | <gh_stars>10-100
/**
* @author ooooo
* @date 2021/5/25 22:22
*/
#ifndef CPP_1870__SOLUTION1_H_
#define CPP_1870__SOLUTION1_H_
#include <iostream>
#include <vector>
using namespace std;
class Solution {
public:
int minSpeedOnTime(vector<int> &dist, double hour) {
if (dist.size() - 1 >= hour) return -1;
int l = 1, r = *max_element(dist.begin(), dist.end()) * 100;
int ans = 0;
while (l <= r) {
int mid = l + (r - l) / 2;
double sum = 0;
for (int i = 0; i < dist.size() - 1; i++) {
int d = dist[i];
int v = d % mid == 0 ? d / mid : d / mid + 1;
sum += v;
}
sum += dist[dist.size() - 1] * 1.0 / mid;
if (sum <= hour) {
ans = mid;
r = mid - 1;
} else {
l = mid + 1;
}
}
return ans;
};
#endif //CPP_1870__SOLUTION1_H_
|