HDU 1081 To The Max 最大子矩阵和 .

题目地址：http://acm.hdu.edu.cn/showproblem.php?pid=1081

#include <iostream>
#include <algorithm>
#include <cstring>
#include <cstdio>
using namespace std;
const int maxn=100+5;
const int INF=0x3f3f3f3f;
int Grid[maxn][maxn],d[maxn];
int MaxSum(int n)
{
int ans=-INF,temp=0;
for(int i=0;i<n;i++){
if(temp>0) temp+=d[i];
else temp=d[i];
ans=max(ans,temp);
}
return ans;
}
int solve(int n)
{
int ans=-INF;
for(int i=0;i<n;i++)
{
memset(d,0,sizeof(d));
for(int j=i;j<n;j++)
{
for(int k=0;k<n;k++)
d[k]+=Grid[j][k];

ans=max(ans,MaxSum(n));
}
}
return ans;
}
int main(int argc, char const *argv[])
{
int n;
while(cin>>n)
{
for(int i=0;i<n;i++)
for(int j=0;j<n;j++)
scanf("%d",&Grid[i][j]);
cout<<solve(n)<<endl;;
}
return 0;
}