Submission #851995

#	Time	Username	Problem	Language	Result	Execution time	Memory
851995		stdfloat	Bitaro the Brave (JOI19_ho_t1)	C++17	100 / 100	97 ms	89680 KiB

joi2019_ho_t1

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

using ll = long long;

int32_t main() {
	ios::sync_with_stdio(false); cin.tie(nullptr);

	int n, m;
	cin >> n >> m;

	vector<string> a(n);
	for (int i = 0; i < n; i++) {
		cin >> a[i];
	}

	vector<vector<int>> cntI(n, vector<int>(m)), cntO(n, vector<int>(m));
	for (int i = n - 1; i >= 0; i--) {
		for (int j = m - 1; j >= 0; j--) {
			cntI[i][j] += (i + 1 < n ? cntI[i + 1][j] : 0) + (a[i][j] == 'I');
			cntO[i][j] += (j + 1 < m ? cntO[i][j + 1] : 0) + (a[i][j] == 'O');
		}
	}

	ll ans = 0;
	for (int i = 0; i < n; i++) {
		for (int j = 0; j < m - 1; j++) {
			if (a[i][j] == 'J') ans += 1LL * cntO[i][j] * cntI[i][j];
		}
	}

	cout << ans;
}

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