题解 | #矩阵乘法#

矩阵的乘法 按照矩阵乘法规则

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
            int oneLine = in.nextInt();
            int oneLieandNextline = in.nextInt();
            int nextLie = in.nextInt();
            int[][] A = new int[oneLine][oneLieandNextline];
            int[][] B = new int[oneLieandNextline][nextLie];
            for (int i = 0; i < oneLine; i++) {
                for (int j = 0; j < oneLieandNextline; j++) {
                    A[i][j] = in.nextInt();
                }
            }
            for (int i = 0; i < oneLieandNextline; i++) {
                for (int j = 0; j < nextLie; j++) {
                    B[i][j] = in.nextInt();
                }
            }
            int[][] result = function(A, B);
            for (int i = 0; i < result.length; i++) {
                for (int j = 0; j < result[0].length; j++) {
                    System.out.print(result[i][j] + " ");
                }
                 System.out.println("");
            }
            
        }
    }
    public static int[][] function(int[][] A, int[][] B) {
        int aLen = A.length;
        int aLie = A[0].length;
        int bLine = B.length;
        int bLie = B[0].length;
        int[][] result = new int[aLen][bLie];
            for (int i = 0; i < aLen; i++) {
                for (int j = 0; j < bLie; j++) {
                    for (int k = 0; k < bLine; k++) {
                         result[i][j] += A[i][k] * B[k][j];
                    }
                }
            }
        return result;
    }
}