Problem p00116 (C++) — buggy submission, verdict: Time Limit Exceeded

#include <bits/stdc++.h>

using namespace std;

#define INF 1001000100010001000
#define MOD 1000000007
#define EPS 1e-10
#define int long long
#define rep(i, N) for (int i = 0; i < N; i++)
#define Rep(i, N) for (int i = 1; i < N; i++)
#define For(i, a, b) for (int i = (a); i < (b); i++)
#define pb push_back
#define eb emplece_back
#define mp make_pair
#define i_i pair<int, int>
#define vi vector<int>
#define vvi vector<vi>
#define vb vector<bool>
#define vvb vector<vb>
#define vp vector<i_i>
#define Edge pair<i_i, int>
#define all(a) (a).begin(), (a).end()
#define Int(x)                                                                 \\
  int x;                                                                       \\
  scanf("%lld", &x);
#define int2(x, y)                                                             \\
  int x, y;                                                                    \\
  scanf("%lld %lld", &x, &y);
#define fir first
#define sec second
#define ffir first.first
#define fsec first.second
#define sfir second.first
#define ssec second.second

// int dxy[5] = {0, 1, 0, -1, 0};
//  assign

signed main() {
  int2(a, b);
  while (a) {
    a++;
    b++;
    vvi dp(a, vi(b, 0));
    Rep(i, a) {
      string st;
      cin >> st;
      rep(j, st.size()) {
        if (st[j] == '*') {
          dp[i][j + 1]++;
        }
      }
    }
    Rep(i, a) {
      Rep(j, b) { dp[i][j] += dp[i][j - 1]; }
    }
    Rep(j, b) {
      Rep(i, a) { dp[i][j] += dp[i - 1][j]; }
    }
    //     rep(i, a) {rep(j, b) {cout << dp[i][j] << " "; } cout << endl;}

    int ans = 0;
    /*
        int ans = -INF;
        Rep(i, n) {
            Rep(j, n) {
                rep(k, i+1) {
                    rep(l, j+1) {
                        int tmp = -INF;
                        if (i == k && j == l) {
                            continue;
                        } else if (i == k || j == l) {
                            tmp = data[i][j] - data[k][l];
                        } else {
                            tmp = data[i][j] - data[k][j]
                                - data[i][l] + data[k][l];
                        }
                        ans = max(ans, tmp);
                    }
                }
            }
        }
    */
    Rep(st, a) {
      rep(sz, (a - st)) {
        //              cout << "(" << st << " , " << sz << ")" << endl;
        int l = 1, r = 1;
        while (r < b) {
          int tmp = 0;
          tmp = dp[st + sz][r] - dp[st + sz][l - 1] - dp[st - 1][r] +
                dp[st - 1][l - 1];
          while (r < b && !tmp) {
            ans = max(ans, ((r - l + 1) * (sz + 1)));
            r++;
            tmp = dp[st + sz][r] - dp[st + sz][l - 1] - dp[st - 1][r] +
                  dp[st - 1][l - 1];
          }
          //                   cout << "(" << st << "," << l << ")";
          //                    cout << "(" << st+sz << "," << r << ")" << " ";
          // ans = max(ans, ((r - l) * (sz+1)));
          l = ++r;
          // r++;
        }
        //             cout << endl;
      }
    }

    cout << ans << endl;
    cin >> a >> b;
  }

  return 0;
}

Error: TLE

Fixed submission:

#include <bits/stdc++.h>

using namespace std;

#define INF 1001000100010001000
#define MOD 1000000007
#define EPS 1e-10
#define int long long
#define rep(i, N) for (int i = 0; i < N; i++)
#define Rep(i, N) for (int i = 1; i < N; i++)
#define For(i, a, b) for (int i = (a); i < (b); i++)
#define pb push_back
#define eb emplece_back
#define mp make_pair
#define i_i pair<int, int>
#define vi vector<int>
#define vvi vector<vi>
#define vb vector<bool>
#define vvb vector<vb>
#define vp vector<i_i>
#define Edge pair<i_i, int>
#define all(a) (a).begin(), (a).end()
#define Int(x)                                                                 \\
  int x;                                                                       \\
  scanf("%lld", &x);
#define int2(x, y)                                                             \\
  int x, y;                                                                    \\
  scanf("%lld %lld", &x, &y);
#define fir first
#define sec second
#define ffir first.first
#define fsec first.second
#define sfir second.first
#define ssec second.second

// int dxy[5] = {0, 1, 0, -1, 0};
//  assign

signed main() {
  int2(a, b);
  while (a) {
    a++;
    b++;
    vvi dp(a, vi(b, 0));
    Rep(i, a) {
      string st;
      cin >> st;
      rep(j, st.size()) {
        if (st[j] == '*') {
          dp[i][j + 1]++;
        }
      }
    }
    Rep(i, a) {
      Rep(j, b) { dp[i][j] += dp[i][j - 1]; }
    }
    Rep(j, b) {
      Rep(i, a) { dp[i][j] += dp[i - 1][j]; }
    } /*
    rep(i, a) {
        rep(j, b) {
            cout << dp[i][j] << " ";
        }
        cout << endl;
    } */

    int ans = 0;
    Rep(i, a) {
      Rep(j, b) {
        if (!dp[i][j]) {
          ans = max(ans, i * j);
        }
      }
    }

    Rep(i, a) {
      Rep(j, b) {
        rep(k, i + 1) {
          rep(l, j + 1) {
            //             cout << i << j << k << l << " ";
            if (k == i && l == j) {
              continue;
            }
            int tmp;
            if (i == k || j == l) {
              tmp = dp[i][j] - dp[k][l];
            } else {
              tmp = dp[i][j] - dp[i][l] - dp[k][j] + dp[k][l];
            }
            if (!tmp) {
              //                cout << (i - k) * (j - l) << endl;
              ans = max(ans, (i - k) * (j - l));
            }
          }
        }
      }
    }
    cout << ans << endl;
    cin >> a >> b;
  }

  return 0;
}