激光炸弹

Q

A

#include<iostream>
#include<cstring>
#include<algorithm>
using namespace std;
const int N = 5e3 + 10;
int s[N][N];
int n, r;

int main() {
	ios::sync_with_stdio(false);
	cin.tie(0);
	cin >> n >> r;
	r = min(5001, r);
	for (int i = 0; i < n; ++i) {
		int x, y, w;
		cin >> x >> y >> w;
		s[++x][++y] += w;
	}
	for (int i = 1; i <= 5001; ++i) {
		for (int j = 1; j	<= 5001; ++j) {
			s[i][j] += s[i - 1][j] + s[i][j - 1] - s[i - 1][j - 1];
		}
	}
	int ans = 0;
	for (int i = r; i <= 5001; ++i) {
		for (int j = r; j <= 5001; ++j) {
			ans = max(ans, s[i][j] - s[i - r][j] - s[i][j - r] + s[i - r][j - r]	);

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

}