Problem p02618 (C++) — buggy submission, verdict: Time Limit Exceeded

#define _CRT_SECURE_NO_WARNINGS
#include <algorithm>
#include <functional>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <string>
#include <vector>
#define _USE_MATH_DEFINES
#include <bitset>
#include <deque>
#include <iostream>
#include <list>
#include <map>
#include <math.h>
#include <queue>
#include <set>
using namespace std;
typedef long long ll;
#define rep(i, a, b) for (auto i = a; i < b; i++)
#define all(_x) _x.begin(), _x.end()
#define r_sort(_x) sort(_x.begin(), _x.end(), std::greater<int>())
#define vec_cnt(_a, _n) (upper_bound(all(_a), _n) - lower_bound(all(_a), _n))
#define vec_unique(_a) _a.erase(std::unique(all(_a)), _a.end());
#define vvec vector<vector<ll>>
ll gcd(ll a, ll b) { return a % b == 0 ? b : gcd(b, a % b); }
ll lcm(ll a, ll b) { return (a / gcd(a, b)) * b; }
#define INF 1 << 30
const int mod = 1000000007;
ll power(ll x, ll p) {
  ll a = 1;
  while (p > 0) {
    if (p % 2 == 0) {
      x *= x;
      p /= 2;
    } else {
      a *= x;
      p--;
    }
  }
  return a;
}
ll mpower(ll x, ll p) {
  ll a = 1;
  while (p > 0) {
    if (p % 2 == 0) {
      x = x * x % mod;
      p /= 2;
    } else {
      a = a * x % mod;
      p--;
    }
  }
  return a;
}
ll ac(ll n, ll k) {
  ll a = 1;
  rep(i, 1, k) {
    a *= n - i + 1;
    a /= i;
  }
  return a;
}
ll mc(ll n, ll m) {
  ll k = 1, l = 1;
  rep(i, n - m + 1, n + 1) k = k * i % mod;
  rep(i, 1, m + 1) l = l * i % mod;
  l = mpower(l, mod - 2);
  return k * l % mod;
}
int D;
vector<int> c(26);
vector<int> last(26, 0);
vector<vector<int>> s(365, vector<int>(26));
void input();
int score;
int next_num;
const int Way = 12;
const int Nest = 3;
/*void dfs(int nest, int d) {
        int M = 0, temp = score;
        int prev, n;
        vector<pair<int, int>> kouho(26);
        rep(j, 0, 26) {
                score = temp;
                score += s[d - 1][j];
                prev = last[j];
                last[j] = d;
                rep(k, 0, 26)score -= c[k] * (d - last[k]);
                kouho[j].first = score;
                kouho[j].second = j;
                last[j] = prev;
        }
        //sort(all(kouho), greater<pair<int, int>>());
        rep(j, 0, Way) {
                //prev = last[kouho[j].second];
                //last[kouho[j].second] = d;
                score = kouho[j].first;
                if (nest && d < D)dfs(nest - 1, d + 1);
                if (M < score)M = score, n = kouho[j].second;
                printf("j:%2d score:%d\\n", j, score);
                //last[kouho[j].second] = prev;
        }
        score = M;
        next_num = n;
}*/
int dfs(int nest, int i) {
  ll M = -1 << 30, temp = score;
  int prev, p;
  vector<pair<int, int>> kouho(26);
  rep(j, 0, 26) {
    score = temp + s[i - 1][j];
    rep(k, 0, 26) if (j != k) score -= c[k] * (i - last[k]);
    kouho[j].first = score;
    kouho[j].second = j;
  }
  sort(all(kouho), greater<pair<int, int>>());
  rep(j, 0, Way) {
    score = kouho[j].first;
    prev = last[kouho[j].second];
    last[kouho[j].second] = i;
    if (nest && i < D)
      dfs(nest - 1, i + 1);
    last[kouho[j].second] = prev;
    if (M < score)
      M = score, p = kouho[j].second;
  }
  score = M;
  return p;
}
int main() {
  input();
  /*rep(i, 1, D + 1) {
          //score = 0;
          dfs(Nest, i);
          printf("%d\\n", next_num + 1);
          last[next_num] = i;
          printf("%d\\n", score);
  }*/
  rep(i, 1, D + 1) {
    score = 0;
    int p = dfs(Nest, i);
    last[p] = i;
    printf("%d\\n", p + 1);
    // printf("%d\\n", score);
  }
  return 0;
}
void input() {
  cin >> D;
  rep(i, 0, 26) cin >> c[i];
  rep(i, 0, D) { rep(i2, 0, 26) cin >> s[i][i2]; }
}

Error: TLE

Fixed submission:

#define _CRT_SECURE_NO_WARNINGS
#include <algorithm>
#include <functional>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <string>
#include <vector>
#define _USE_MATH_DEFINES
#include <bitset>
#include <deque>
#include <iostream>
#include <list>
#include <map>
#include <math.h>
#include <queue>
#include <set>
using namespace std;
typedef long long ll;
#define rep(i, a, b) for (auto i = a; i < b; i++)
#define all(_x) _x.begin(), _x.end()
#define r_sort(_x) sort(_x.begin(), _x.end(), std::greater<int>())
#define vec_cnt(_a, _n) (upper_bound(all(_a), _n) - lower_bound(all(_a), _n))
#define vec_unique(_a) _a.erase(std::unique(all(_a)), _a.end());
#define vvec vector<vector<ll>>
ll gcd(ll a, ll b) { return a % b == 0 ? b : gcd(b, a % b); }
ll lcm(ll a, ll b) { return (a / gcd(a, b)) * b; }
#define INF 1 << 30
const int mod = 1000000007;
ll power(ll x, ll p) {
  ll a = 1;
  while (p > 0) {
    if (p % 2 == 0) {
      x *= x;
      p /= 2;
    } else {
      a *= x;
      p--;
    }
  }
  return a;
}
ll mpower(ll x, ll p) {
  ll a = 1;
  while (p > 0) {
    if (p % 2 == 0) {
      x = x * x % mod;
      p /= 2;
    } else {
      a = a * x % mod;
      p--;
    }
  }
  return a;
}
ll ac(ll n, ll k) {
  ll a = 1;
  rep(i, 1, k) {
    a *= n - i + 1;
    a /= i;
  }
  return a;
}
ll mc(ll n, ll m) {
  ll k = 1, l = 1;
  rep(i, n - m + 1, n + 1) k = k * i % mod;
  rep(i, 1, m + 1) l = l * i % mod;
  l = mpower(l, mod - 2);
  return k * l % mod;
}
int D;
vector<int> c(26);
vector<int> last(26, 0);
vector<vector<int>> s(365, vector<int>(26));
void input();
int score;
int next_num;
const int Way = 9;
const int Nest = 6;
/*void dfs(int nest, int d) {
        int M = 0, temp = score;
        int prev, n;
        vector<pair<int, int>> kouho(26);
        rep(j, 0, 26) {
                score = temp;
                score += s[d - 1][j];
                prev = last[j];
                last[j] = d;
                rep(k, 0, 26)score -= c[k] * (d - last[k]);
                kouho[j].first = score;
                kouho[j].second = j;
                last[j] = prev;
        }
        //sort(all(kouho), greater<pair<int, int>>());
        rep(j, 0, Way) {
                //prev = last[kouho[j].second];
                //last[kouho[j].second] = d;
                score = kouho[j].first;
                if (nest && d < D)dfs(nest - 1, d + 1);
                if (M < score)M = score, n = kouho[j].second;
                printf("j:%2d score:%d\\n", j, score);
                //last[kouho[j].second] = prev;
        }
        score = M;
        next_num = n;
}*/
int dfs(int nest, int i) {
  ll M = -1 << 30, temp = score;
  int prev, p;
  vector<pair<int, int>> kouho(26);
  rep(j, 0, 26) {
    score = temp + s[i - 1][j];
    rep(k, 0, 26) if (j != k) score -= c[k] * (i - last[k]);
    kouho[j].first = score;
    kouho[j].second = j;
  }
  sort(all(kouho), greater<pair<int, int>>());
  rep(j, 0, Way) {
    score = kouho[j].first;
    prev = last[kouho[j].second];
    last[kouho[j].second] = i;
    if (nest && i < D)
      dfs(nest - 1, i + 1);
    last[kouho[j].second] = prev;
    if (M < score)
      M = score, p = kouho[j].second;
  }
  score = M;
  return p;
}
int main() {
  input();
  /*rep(i, 1, D + 1) {
          //score = 0;
          dfs(Nest, i);
          printf("%d\\n", next_num + 1);
          last[next_num] = i;
          printf("%d\\n", score);
  }*/
  rep(i, 1, D + 1) {
    score = 0;
    int p = dfs(Nest, i);
    last[p] = i;
    printf("%d\\n", p + 1);
    // printf("%d\\n", score);
  }
  return 0;
}
void input() {
  cin >> D;
  rep(i, 0, 26) cin >> c[i];
  rep(i, 0, D) { rep(i2, 0, 26) cin >> s[i][i2]; }
}