题解 | #矩阵乘法#

import java.util.Scanner;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int x = sc.nextInt();//第一个矩阵的行
        int y = sc.nextInt();//第一个矩阵的列、第二个矩阵的行
        int z = sc.nextInt();//第二个矩阵额列

        //构建第一个矩阵
        int[][] jz1 = new int[x][y];
        for (int i = 0; i < x; i++) {
            for (int j = 0; j < y; j++) {
                jz1[i][j] = sc.nextInt();
            }
        }
        int[][] jz2 = new int[y][z];
        for (int i = 0; i < y; i++) {
            for (int j = 0; j < z; j++) {
                jz2[i][j] = sc.nextInt();
            }
        }

        //新矩阵x行、z列
        int[][] newJz = new int[x][z];
        for (int i = 0; i < x; i++) {
            for (int j = 0; j < z; j++) {
                for (int k = 0; k < y; k++) {
                    newJz[i][j] += jz1[i][k] * jz2[k][j]; //关键
                }
            }
        }

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