题目:返回一个二维整数数组中最大子数组的和。

#include<iostream>    
#include<ctime>
using namespace std;
#define M 4
#define N 4

int maxline(int *array, int len)       //求一维数组最大子序列和  
{
    int i, sum = array[0], b = 0,j = 0;
    for (i = 0; i<len; ++i)
    {
        if (b>0)
            b += array[i];
        else
            b = array[i];
        if (b>sum)
            sum = b;            
    }
    return sum;
}
int maxtwodimension(int n, int m, int array[M][N])
{
    int i, j, h,g, max, sum = -1000;
    int b[100];
    for(g = 0;g < m;g++){
        for (i = 0; i<n; i++)
        {
            memset(b, 0, sizeof(b));       //将b[100]中的数字全部初始化为0  
            for (j = i; j<n; j++)          //把第i行到第n行相加,对每一次相加求出最大值  
            {
                for (h = g; h<m; h++)
                {
                    b[h] += array[j][h];   //求一行的和，二维数组压缩成一维数组  
                }
                max = maxline(b, h);   //按照一维数组求最大子数组的方法，求最大子序列和

                if (max>sum)
                    sum = max;
            }
        }
    }

    return sum;
}
int main()
{
    int arr[M][N];
    cout << "随机二维数组为：" << endl;
    srand((unsigned)time(0));
    for (int i = 0; i < M; i++)
    {
        for (int j = 0; j < N; j++)
        {
            arr[i][j] = rand() % 100-25;
            cout << arr[i][j] << " ";
        }
        cout << endl;
    }
    cout <<"最大子矩阵和为：  "<< maxtwodimension(M, N, arr) << endl;
    return 0;
}