Submission #1278627

#	Time	Username	Problem	Language	Result	Execution time	Memory
1278627		IBory	Bitaro the Brave (JOI19_ho_t1)	C++20	100 / 100	253 ms	79792 KiB

joi2019_ho_t1

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

const int MAX = 3003;
char C[MAX][MAX];
int Ocnt[MAX][MAX], Icnt[MAX][MAX];

int main() {
	ios::sync_with_stdio(0); cin.tie(0);
	int N, M;
	cin >> N >> M;
	for (int i = 1; i <= N; ++i) for (int j = 1; j <= M; ++j) cin >> C[i][j];
	for (int i = 1; i <= N; ++i) for (int j = M; j > 0; --j) Ocnt[i][j] = Ocnt[i][j + 1] + (C[i][j] == 'O');
	for (int j = 1; j <= M; ++j) for (int i = N; i > 0; --i) Icnt[i][j] = Icnt[i + 1][j] + (C[i][j] == 'I');
	ll ans = 0;
	for (int i = 1; i <= N; ++i) for (int j = 1; j <= M; ++j) {
		if (C[i][j] == 'J') ans += Ocnt[i][j] * Icnt[i][j];
	}
	cout << ans;
	return 0;
}

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