Submission #878693

#	Time	Username	Problem	Language	Result	Execution time	Memory
878693		frostray8653	Bitaro the Brave (JOI19_ho_t1)	C++17	100 / 100	199 ms	89164 KiB

joi2019_ho_t1

#include <bits/stdc++.h>
#define int long long
#define IO ios::sync_with_stdio(0), cin.tie(0)
#define FOR(i, a, b) for (int i = a, I = b; i <= I; i++)
using namespace std;
using pii = pair<int, int>;
void dbg() {;}
template<class T, class ...U>
void dbg(T a, U ...b) { cout << a << " "; dbg(b...); }
void ent() { cout << "\n"; }

const int N = 3005;
char a[N][N];
int j_sum[N][N];

signed main() {
    IO;

    int n, m;
    cin >> n >> m;
    FOR(i, 1, n)
        FOR(j, 1, m)
            cin >> a[i][j];
    
    for (int i = 1; i <= n; i++) {
        int O_cnt = 0;
        for (int j = m; j >= 1; j--) {
            if (a[i][j] == 'O')
                O_cnt += 1;
            else if (a[i][j] == 'J')
                j_sum[i][j] = O_cnt;
        }
    }
    int ans = 0;
    for (int j = 1; j <= m; j++) {
        for (int i = 1; i <= n; i++) {
            j_sum[i][j] += j_sum[i - 1][j];
            if (a[i][j] == 'I')
                ans += j_sum[i][j];
        }
    }
    cout << ans << "\n";

    return 0;
}

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