Submission #763661

#	Time	Username	Problem	Language	Result	Execution time	Memory
763661		Blagoj	Bitaro the Brave (JOI19_ho_t1)	C++17	100 / 100	221 ms	89392 KiB

joi2019_ho_t1

#include <bits/stdc++.h>

#pragma GCC optimize("Ofast,unroll-loops")

using namespace std;

#define endl '\n'
#define ll long long
#define all(x) x.begin(), x.end()

int col[3002][3002], row[3002][3002];

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    int n, m;
    cin >> n >> m;
    vector<string> v(n);
    for (int i = 0; i < n; i++) cin >> v[i];
    for (int i = 0; i < n; i++) {
        for (int j = m - 1; j >= 0; j--) {
            row[i][j] = row[i][j + 1];
            row[i][j] += (v[i][j] == 'O');
        }
    }
    for (int j = 0; j < m; j++) {
        for (int i = n - 1; i >= 0; i--) {
            col[i][j] += col[i + 1][j];
            col[i][j] += (v[i][j] == 'I');
        }
    }
    ll ans = 0;
    for (int i = 0; i < n - 1; i++) {
        for (int j = 0; j < m - 1; j++) {
            if (v[i][j] == 'J') ans += row[i][j + 1] * col[i + 1][j];
        }
    }
    cout << ans;
}

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