Submission #477863

#	Time	Username	Problem	Language	Result	Execution time	Memory
477863		BThero	Orchard (NOI14_orchard)	C++17	12 / 25	1097 ms	12164 KiB

orchard

#include <bits/stdc++.h>

#define pb push_back
#define all(x) (x).begin(), (x).end()
#define sz(x) (int)(x).size()

using namespace std;

typedef long long ll;

int main() {
	ios::sync_with_stdio(0);
	cin.tie(0);
	int n, m;
	cin >> n >> m;
	vector<vector<int>> a(n, vector<int>(m, 0));
	vector<vector<int>> p(n, vector<int>(m, 0));

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

	int ans = (int)1e9;
	int cnt = 0;

	for (int i = 0; i < n; i++) {
		for (int j = 0; j < m; j++) {
			cnt += a[i][j];

			if (a[i][j] == 1) {
				a[i][j] = -1;
			}
			else {
				a[i][j] = 1;
			}
		}
	}

	for (int i = 0; i < n; i++) {
		for (int j = 0; j < m; j++) {
			p[i][j] = a[i][j]
			+ (i > 0 ? p[i - 1][j] : 0)
			+ (j > 0 ? p[i][j - 1] : 0)
			- (i > 0 && j > 0 ? p[i - 1][j - 1] : 0);
		}
	}

	for (int x1 = 0; x1 < n; x1++) {
		for (int y1 = 0; y1 < m; y1++) {
			for (int x2 = x1; x2 < n; x2++) {
				for (int y2 = y1; y2 < m; y2++) {
					int cur = p[x2][y2]
					- (x1 > 0 ? p[x1 - 1][y2] : 0)
					- (y1 > 0 ? p[x2][y1 - 1] : 0)
					+ (x1 > 0 && y1 > 0 ? p[x1 - 1][y1 - 1] : 0);
					ans = min(ans, cnt + cur);
				}
			}
		}
	}

	cout << ans << '\n';
	return 0;
}

• Subtask 1: 4 / 4
• Subtask 2: 4 / 4
• Subtask 3: 0 / 5
• Subtask 4: 0 / 3
• Subtask 5: 4 / 4
• Subtask 6: 0 / 5