题解 | #矩阵乘法#

// mark一下

import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        while (in.hasNextLine()) {
            int x = Integer.valueOf(in.nextLine());
            int y = Integer.valueOf(in.nextLine());
            int z = Integer.valueOf(in.nextLine());
            int[][] a = new int[x][y];
            int[][] b = new int[y][z];
            for (int i = 0; i < x; i++) {
                String[] eachLine = in.nextLine().split(" ");
                for (int j = 0; j < y; j++) {
                    a[i][j] = Integer.valueOf(eachLine[j]);
                }
            }

            for (int i = 0; i < y; i++) {
                String[] eachLine = in.nextLine().split(" ");
                for (int j = 0; j < z; j++) {
                    b[i][j] = Integer.valueOf(eachLine[j]);
                }
            }

            int[][] c = new int[x][z];
            for (int i = 0; i < x; i++) {
                for (int j = 0; j < z; j++) {
                    int sum = 0;
                    for (int k = 0; k < y; k++) {
                        sum += (a[i][k] * b[k][j]);
                    }
                    c[i][j] = sum;
                }
            }

            for (int i = 0; i < x; i++) {
                for (int j = 0; j < z; j++) {
                    if (j != z - 1) {
                        System.out.print(c[i][j] + " ");
                    } else {
                        System.out.println(c[i][j]);
                    }
                }
            }
        }
    }
}