Submission #1226692

#	Time	Username	Problem	Language	Result	Execution time	Memory
1226692		wedonttalkanymore	Bitaro the Brave (JOI19_ho_t1)	C++20	0 / 100	0 ms	324 KiB

joi2019_ho_t1

#include <bits/stdc++.h>
using namespace std;
using ll = long long;

const int N = 5005;
int h, w;
int a[N][N];
int col_pfs[N][N][3]; // prefix sum theo cột

signed main() {
    cin >> h >> w;
    for (int i = 1; i <= h; i++) {
        string s;
        cin >> s;
        for (int j = 1; j <= w; j++) {
            if (s[j - 1] == 'J') a[i][j] = 0;
            else if (s[j - 1] == 'O') a[i][j] = 1;
            else a[i][j] = 2;
        }
    }
    for (int j = 1; j <= w; j++) {
        for (int i = 1; i <= h; i++) {
            for (int k = 0; k < 3; k++) {
                col_pfs[i][j][k] = col_pfs[i - 1][j][k];
                if (a[i][j] == k) col_pfs[i][j][k]++;
            }
        }
    }
    ll ans = 0;
    for (int i = 1; i <= h; i++) {
        for (int k = i + 2; k <= h; k++) { 
            for (int j = 1; j <= w; j++) {
                if (a[i][j] == 0 && a[k][j] == 2) {
                    int cntO = col_pfs[k - 1][j][1] - col_pfs[i][j][1];
                    ans += cntO;
                }
            }
        }
    }
    cout << ans;
    return 0;
}

• Subtask 1: 0 / 20
• Subtask 2: 0 / 30
• Subtask 3: 0 / 50