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 in = new Scanner(System.in);
        // 注意 hasNext 和 hasNextLine 的区别
        while (in.hasNextInt()) { // 注意 while 处理多个 case
            // 接收二维数组长度
            int x = in.nextInt();
            int y = in.nextInt();
            int z = in.nextInt();
            // 定义二维数组
            int[][] xy = new int[x][y];
            int[][] yz = new int[y][z];
            int[][] xz = new int[x][z];
            // 获取二维数组值
            for (int i = 0; i < x ; i++) {
                for (int j = 0; j < y; j++) {
                    xy[i][j] = in.nextInt();
                }
            }
            for (int i = 0; i < y ; i++) {
                for (int j = 0; j < z; j++) {
                    yz[i][j] = in.nextInt();
                }
            }
            // 向新的二维数组写入数据
            for (int i = 0 ; i < x ; i++) {
                for (int k = 0 ; k < z ; k++) {
                    int j = 0 ;
                    while(j<y){
                        xz[i][k] += xy[i][j] * yz[j][k];
                        j++;
                    }
                }
            }
            for (int i = 0 ; i < x ; i++) {
                for (int j = 0 ; j < z ; j++) {
                    System.out.print(xz[i][j] + " ");
                }
                System.out.println();
            }
        }
    }
}