Solution.java

class Solution {
    public int[][] solution(int[][] arr1, int[][] arr2) {
        int[][] answer = new int[arr1.length][arr2[0].length];
        
        for (int i = 0; i < answer.length; i++) {
            for (int j = 0; j < answer[0].length; j++) {
                int result = 0;
                for (int k = 0; k < arr1[0].length; k++) {
                    result += arr1[i][k] * arr2[k][j];
                }
                answer[i][j] = result;
            }
        }
        
        return answer;
    }
}

출처: 프로그래머스 코딩 테스트 연습, https://programmers.co.kr/learn/challenges