Problem p02269 (C++) — buggy submission, verdict: Time Limit Exceeded


#include <cstdio>

#include <iostream>

#include <cstring>

using namespace std;

typedef long long ll;

#define row 1001333 // 取一个比h2(k)大的质数

#define col 20

char H[row][col];

ll h1(ll key) { return key % row; }

ll h2(ll key) { return 1 + (key % (row - 1)); }

ll chtonum(char s) { // character to number

  if (s == 'A')
    return 1;

  if (s == 'C')
    return 2;

  if (s == 'G')
    return 3;

  if (s == 'T')
    return 4;

  return 0;
}

ll get_key(char s[]) { // 生成key值

  ll sum = 0, p = 1;

  int len = strlen(s);

  for (ll i = 0; i < len; i++) {

    sum += p * chtonum(s[i]);

    p *= 5;
  }

  return sum;
}

void insert(char s[]) {

  ll key, h;

  key = get_key(s);

  ll i = 0;

  while (1) {

    h = (h1(key) + i * h2(key)) % row; // 根据key值生成对应的位置

    if (strcmp(H[h], s) == 0)
      return; // 这个元素字典里已经有了

    else if (strlen(H[h]) == 0) {

      strcpy(H[h], s); // 如果该位置没有别的值，就把这个元素插进去

      return;
    }

    i++; // 如果这个i对应的h的位置已经有元素了，那么继续寻找下一个i对应的位置
  }
}

bool find(char s[]) {

  ll key, h;

  key = get_key(s);

  ll i = 0;

  while (1) {

    h = (h1(key) + i * h2(key)) % row;

    if (strcmp(H[h], s) == 0)
      return true; // 如果找到了该元素

    else if (strlen(H[h]) == 0)
      return false;

    i++;
  }

  return false;
}

int main() {

  int n;

  char c[20], s[20];

  for (int i = 0; i < row; i++)
    H[i][0] = '\\0'; // 把数组初始化 方便比较

  scanf("%d", &n);

  for (int i = 0; i < n; i++) {

    cin >> c >> s;

    if (c[0] == 'i')
      insert(s);

    else {

      if (find(s))
        cout << "yes" << endl;

      else
        cout << "no" << endl;
    }
  }

  return 0;
}


Error: TLE

Fixed submission:


#include <cstdio>

#include <iostream>

#include <cstring>

using namespace std;

typedef long long ll;

#define row 1001333 // 取一个比h2(k)大的质数

#define col 20

char H[row][col];

ll h1(ll key) { return key % row; }

ll h2(ll key) { return 1 + (key % (row - 1)); }

ll chtonum(char s) { // character to number

  if (s == 'A')
    return 1;

  if (s == 'C')
    return 2;

  if (s == 'G')
    return 3;

  if (s == 'T')
    return 4;

  return 0;
}

ll get_key(char s[]) { // 生成key值

  ll sum = 0, p = 1;

  int len = strlen(s);

  for (ll i = 0; i < len; i++) {

    sum += p * chtonum(s[i]);
  }

  return sum;
}

void insert(char s[]) {

  ll key, h;

  key = get_key(s);

  ll i = 0;

  while (1) {

    h = (h1(key) + i * h2(key)) % row; // 根据key值生成对应的位置

    if (strcmp(H[h], s) == 0)
      return; // 这个元素字典里已经有了

    else if (strlen(H[h]) == 0) {

      strcpy(H[h], s); // 如果该位置没有别的值，就把这个元素插进去

      return;
    }

    i++; // 如果这个i对应的h的位置已经有元素了，那么继续寻找下一个i对应的位置
  }
}

bool find(char s[]) {

  ll key, h;

  key = get_key(s);

  ll i = 0;

  while (1) {

    h = (h1(key) + i * h2(key)) % row;

    if (strcmp(H[h], s) == 0)
      return true; // 如果找到了该元素

    else if (strlen(H[h]) == 0)
      return false;

    i++;
  }

  return false;
}

int main() {

  int n;

  char c[20], s[20];

  for (int i = 0; i < row; i++)
    H[i][0] = '\\0'; // 把数组初始化 方便比较

  scanf("%d", &n);

  for (int i = 0; i < n; i++) {

    cin >> c >> s;

    if (c[0] == 'i')
      insert(s);

    else {

      if (find(s))
        cout << "yes" << endl;

      else
        cout << "no" << endl;
    }
  }

  return 0;
}