给定一个N阶矩阵A，输出A的M次幂（M是非负整数）（Java）

import java.util.*;

public class Main {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int m = sc.nextInt();
        int[][] arr = new int[n][n];
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < n; j++) {
                arr[i][j] = sc.nextInt();
            }
        }
        if (m == 0) {
            for (int i = 0; i < n; i++) {
                for (int j = 0; j < n; j++) {
                    if (i == j)
                        System.out.print(1 + " ");
                    else
                        System.out.print(0 + " ");
                }
                System.out.println();
            }
            System.exit(0);
        }
        int[][] arr1 = arr;
        for (int i = 1; i < m; i++) {
            arr1 = multiply(arr, arr1);
        }
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < n; j++) {
                System.out.print(arr1[i][j] + " ");
            }
            System.out.println();
        }
    }

    private static int[][] multiply(int[][] a, int[][] b) {
        int len = a.length;
        int[][] res = new int[len][len];
        for (int i = 0; i < len; i++) {
            for (int j = 0; j < len; j++) {
                for (int k = 0; k < len; k++) {
                    res[i][j] += a[i][k] * b[k][j];
                }
            }
        }
        return res;
    }
}