P2280 [HNOI2003]激光炸弹

R63978323

Luogu/P2280/P2280.cpp

@@ -0,0 +1,27 @@
+#include <bits/stdc++.h>
+
+using std::cin;
+using std::cout;
+using std::endl;
+
+int n, m, x, y, v, ans, g[5005][5005];
+
+int main() {
+    cin >> n >> m;
+    for (int i = 1; i <= n; i++) {
+        cin >> x >> y >> v;
+        g[x + 1][y + 1] = v;
+    }
+    for (int i = 1; i <= 5001; i++) {
+        for (int j = 1; j <= 5001; j++) {
+            g[i][j] += g[i][j - 1] + g[i - 1][j] - g[i - 1][j - 1];
+        }
+    }
+    for (int i = m; i <= 5001; i++) {
+        for (int j = m; j <= 5001; j++) {
+            ans = std::max(ans, g[i][j] - g[i - m][j] - g[i][j - m] + g[i - m][j - m]);
+        }
+    }
+    cout << ans << endl;
+    return 0;
+}