new file: 41.cpp

41.cpp

@@ -0,0 +1,24 @@
+// 126
+#include <bits/stdc++.h>
+using namespace std;
+int n, m, k, a[105][105], sum[105][105];
+int query(int xx1, int yy1, int xx2, int yy2)
+{
+    return sum[xx2][yy2] - sum[xx1 - 1][yy2] - sum[xx2][yy1 - 1] + sum[xx1 - 1][yy1 - 1];
+}
+int main()
+{
+    scanf("%d", &n);
+    for (int i = 1; i <= n; ++i)
+        for (int j = 1; j <= n; ++j)
+            scanf("%d", &a[i][j]), sum[i][j] = a[i][j] + sum[i - 1][j] + sum[i][j - 1] - sum[i - 1][j - 1];
+    int ans = -2147482648;
+    for (int xx1 = 1; xx1 <= n; ++xx1)
+        for (int yy1 = 1; yy1 <= n; ++yy1)
+            for (int xx2 = xx1; xx2 <= n; ++xx2)
+                for (int yy2 = yy1; yy2 <= n; ++yy2)
+                    if (query(xx1, yy1, xx2, yy2) > ans)
+                        ans = query(xx1, yy1, xx2, yy2);
+    printf("%d", ans);
+    return 0;
+}