Blue Bridge Cup test questions basic exercises matrix multiplication BASIC-17 JAVA

Foreword

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Exam questions basic exercises matrix multiplication

Resource limit
Time limit: 1.0s Memory limit: 512.0MB

Problem description
　　Given an N-th order matrix A, output A to the power of M (M is a non-negative integer)
　　For example:
　　A =
　　1 2
　　3 4
　　A to the power of 2
　　7 10
　　15 22

Input format The
　　first row is a positive integer N, M (1 <= N <= 30, 0 <= M <= 5), which means the order of the matrix A and the required power. The
　　next N rows, N each row Non-negative integer with an absolute value not exceeding 10, describing the value of matrix A

Output format
　　outputs a total of N rows, with N integers per row, representing the matrix corresponding to the M-th power of A. Adjacent numbers are separated by a space

Sample input
2 2
1 2
3 4

Sample output
7 10
15 22

Code for this question

import java.util.Scanner;

public class MatrixMulti {

    private static int N;//矩阵A的阶数
    private static int[][] matrix; //矩阵A

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        N = sc.nextInt();
        int M = sc.nextInt(); //要求的幂数
        matrix = new int[N][N];
        for (int i = 0; i < N; i++) {
            for (int j = 0; j < N; j++) {
                matrix[i][j] = sc.nextInt();
            }
        }
        int[][] newMatrix = new int[N][N];
        if (M == 0) {
            for (int i = 0; i < N; i++) {
                newMatrix[i][i] = 1;
            }
        } else {
            newMatrix = matrix;
            for (int i = 0; i < M - 1; i++) {
                newMatrix = matriMultiplication(newMatrix);
            }
        }

        for (int i = 0; i < N; i++) {
            for (int j = 0; j < N; j++) {
                System.out.print(newMatrix[i][j] + " ");
            }
            System.out.println();
        }
    }

    private static int[][] matriMultiplication(int[][] matrixParam) {
        int[][] newMatrix = new int[N][N];
        for (int i = 0; i < N; i++) {
            for (int j = 0; j < N; j++) {
                for (int k = 0; k < N; k++) {
                    newMatrix[i][k] += matrixParam[i][j] * matrix[j][k];
                }
            }
        }
        return newMatrix;
    }
}