51Nod－1051－最大子矩阵和

描述

题解

代码

#include <iostream>
#include <cstdio>

typedef long long ll;

using namespace std;

const int MAXN = 505;

ll Matrix[MAXN][MAXN];

int main(int argc, const char * argv[])
{
//    freopen("input.txt", "r", stdin);
//    freopen("input.txt", "w", stdin);
int M, N;
cin >> M >> N;
int A;
for (int i = 1; i <= N; i++)
{
for (int j = 1; j <= M; j++)
{
scanf("%d", &A);
Matrix[i][j] = Matrix[i - 1][j] + A;
}
}
long long ans = 0;
for (int i = 1; i <= N; i++)
{
for (int j = i; j <= N; j++)
{
int sum = 0;
for (int k = 1; k <= M; k++)
{
sum += Matrix[j][k] - Matrix[i - 1][k];
if (sum < 0)
{
sum = 0;
}
else if (sum > ans)
{
ans = sum;
}
}
}
}

std::cout << ans << '\n';
return 0;
}