Submission #101654

#	Time	Username	Problem	Language	Result	Execution time	Memory
101654		KCSC	Bitaro the Brave (JOI19_ho_t1)	C++14	100 / 100	473 ms	88440 KiB

joi2019_ho_t1

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

const int DIM = 3005;

char mat[DIM][DIM];
int psm1[DIM][DIM], psm2[DIM][DIM];

int main(void) {
#ifdef HOME
	freopen("brave.in", "r", stdin);
	freopen("brave.out", "w", stdout);
#endif
	int n, m; cin >> n >> m;
	for (int i = 1; i <= n; ++i) {
		cin >> (mat[i] + 1); }
	long long ans = 0;
	for (int i = n; i >= 1; --i) {
		for (int j = m; j >= 1; --j) {
			psm1[i][j] = psm1[i][j + 1] + (mat[i][j] == 'O');
			psm2[i][j] = psm2[i + 1][j] + (mat[i][j] == 'I');	
			if (mat[i][j] == 'J') {
				ans += psm1[i][j] * psm2[i][j]; } } }
	cout << ans << endl;
	return 0; }

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