delete pics to save space

7.1050.cpp

@@ -0,0 +1,28 @@
+#include<cstdio>
+#include<algorithm>
+using namespace std;
+const int maxn=105;
+int n,a[maxn][maxn],s[maxn][maxn],res;
+int main()
+{
+#ifdef local
+	freopen("pro.in","r",stdin);
+#endif
+	scanf("%d",&n);
+	for(int i=1;i<=n;i++) for(int j=1;j<=n;j++) scanf("%d",&a[i][j]);
+	for(int i=1;i<=n;i++) for(int j=1;j<=n;j++) s[i][j]=s[i][j-1]+a[i][j];
+	res=s[1][1];
+	for(int i=1;i<=n;i++) for(int j=i;j<=n;j++)
+	{
+		int tot=s[1][j]-s[1][i-1],now=tot;
+		for(int k=2;k<=n;k++)
+		{
+			if(tot<0) tot=0;
+			tot+=s[k][j]-s[k][i-1];
+			now=max(tot,now);
+		}
+		res=max(now,res);
+	}
+	printf("%d\n",res);
+	return 0;
+}