프로그래머스) Lv3 - 행렬의 곱셈

https://programmers.co.kr/learn/courses/30/lessons/12949

코딩테스트 연습 - 행렬의 곱셈

 

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C++ 소스 코드

#include <string>
#include <vector>

using namespace std;

vector<vector<int>> solution(vector<vector<int>> arr1, vector<vector<int>> arr2) {
    vector<vector<int>> answer;
    int r = (int) arr1.size();
    int c = (int) arr2[0].size();
    vector<int> a;
    a.resize(c,0);
    answer.resize(r,a);
    for (int i = 0; i < arr1.size(); i++){
        for (int j = 0; j < arr2[0].size(); j++){
            for (int k = 0; k < arr1[0].size(); k++){
                answer[i][j] += arr1[i][k] * arr2[k][j];
            }
        }
    }
    return answer;
}

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Swift 소스 코드

import Foundation

func solution(_ arr1:[[Int]], _ arr2:[[Int]]) -> [[Int]] {
    var answer = [[Int]](repeating: [Int](repeating: 0, count: arr2[0].count),count: arr1.count)
    for i in 0..<arr1.count {
        for j in 0..<arr2[0].count {
            for k in 0..<arr1[0].count {
                answer[i][j] += arr1[i][k]*arr2[k][j]
            }
        }
    }
    return answer
}