poj1050 二维数组最大子序列矩阵和

public class Main {

    public int findMaxSumOneDimensions(int[] arr) {
        int len = arr.length;
        int max = arr[0], sum = max;
        for (int i = 1; i < len; i++) {
            sum += arr[i];
            if (sum < 0)
                sum = arr[i];
            if (max <= sum)
                max = sum;
        }
        return max;
    }

    public int findMaxSumTwoDimensions(int[][] arr, int N) {
        int max = 0;
        int[] b = new int[N];
        for (int i = 0; i < N; i++) {
            for (int j = 0; j < N; j++)
                b[j] = 0;
            for (int j = i; j < N; j++) {
                for (int k = 0; k < N; k++)
                    b[k] += arr[j][k];
                int temp = findMaxSumOneDimensions(b);
                if (temp >= max)
                    max = temp;
            }
        }
        return max;
    }

    public static void main(String[] args) throws FileNotFoundException {
        // Scanner scanner = new Scanner(new BufferedInputStream(new
        // FileInputStream(new File("E:\\input.txt"))));
        Main main = new Main();
        Scanner scanner = new Scanner(new BufferedInputStream(System.in));
        int N = scanner.nextInt();
        int[][] arr = new int[N][N];
        for (int i = 0; i < N; i++) {
            for (int j = 0; j < N; j++) {
                arr[i][j] = scanner.nextInt();
            }
        }
        System.out.println(main.findMaxSumTwoDimensions(arr, N));
    }
}