01public static int[][] arrSum(int arr[][]){02    int m = arr.length;03    int n = arr[0].length;04    int p[][] = new int[m+1][n+1];05    p[0][0] = arr[0][0];06    for(int i=0; i<=m; i++) p[i][0] = 0;07    for(int i=0; i<=n; i++) p[0][i] = 0;08    for(int i=1; i<=m; i++){09        for(int j=1; j<=n; j++){10            p[i][j] = p[i-1][j] + p[i][j-1] + arr[i-1][j-1] - p[i-1][j-1];11        }12    }13    return p;14}15//遍历所有二维数组的矩形区域16static int  maxArrSum(int arr[][]){17    int m = arr.length;18    int n = arr[0].length;19    int p[][] = arrSum(arr);20    int ans = Integer.MIN_VALUE;21    for(int i=1; i<=m; i++){22        for(int j=1; j<=n; j++){23            for(int endi=i; endi <=m; endi++){24                for(int endj=j; endj<=n; endj++){25                    int sum = p[endi][endj] - p[i-1][endj] - p[endi][j-1] + p[i-1][j-1];26                    if(ans < sum) ans = sum;27                }28            }29        }30    }31    return ans;32}