Submission #411741

#	Time	Username	Problem	Language	Result	Execution time	Memory
411741		nichke	Bitaro the Brave (JOI19_ho_t1)	C++14	100 / 100	199 ms	160068 KiB

joi2019_ho_t1

#include <bits/stdc++.h>
using namespace std;
#define int long long
#define endl '\n'

int ans;
int h, w;
string ar[3005];
int suff[3005][3005][2];

signed main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cin >> h >> w;
	for (int i = 0; i < h; i++) {
		cin >> ar[i];
	}
	for (int i = 0; i < h; i++) {
		for (int j = w - 1; j >= 0; j--) {
			suff[i][j][0] = suff[i][j + 1][0];
			suff[i][j][0] += (ar[i][j] == 'O');
		}
	}
	for (int i = h - 1; i >= 0; i--) {
		for (int j = 0; j < w; j++) {
			suff[i][j][1] = suff[i + 1][j][1];
			suff[i][j][1] += (ar[i][j] == 'I');
		}
	}
	for (int i = 0; i < h; i++) {
		for (int j = 0; j < w; j++) {
			if (ar[i][j] == 'J') {
				ans += suff[i][j][0] * suff[i][j][1];
			}
		}			
	}
	cout << ans << '\n';
	return 0;
}

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