激光炸弹

 

 1 #include <bits/stdc++.h>
 2 using namespace std;
 3 const int N = 5010;
 4 int g[N][N];
 5 int main() {
 6     int n, r;
 7     cin >> n >> r;
 8     int nn = r, mm = r; //判断边界
 9     for (int i = 0; i < n; i++) {
10         int x, y, w;
11         cin >> x >> y >> w;
12         x++;
13         y++; //前缀和下标从1开始
14         nn = max(nn, x);
15         mm = max(mm, y);
16         g[x][y] += w;
17     }
18     for (int i = 1; i <= nn; i++) {
19         for (int j = 1; j <= mm; j++) {
20             g[i][j] += g[i - 1][j] + g[i][j - 1] - g[i - 1][j - 1]; 
21         }
22     }
23     int res = 0;
24     //枚举所有边长是r的矩形，枚举(i, j)为其右下角
25     for (int i = r; i <= nn; i++) {
26         for (int j = r; j <= mm; j++) {
27             res = max(res, g[i][j] - g[i - r][j] - g[i][j - r] + g[i - r][j - r]);
28         }
29     }
30     cout << res << endl;
31     return 0;
32 }

 

posted @ 2020-11-03 16:30  kyk333  阅读(106)  评论(0)    收藏  举报