[Programmers] 행렬의 곱셈

[Programmers] 행렬의 곱셈

Problem URL : 행렬의 곱셈

#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 = arr1.size();
    int c = arr1[0].size();
    int c2 = arr2[0].size();
    answer.resize(r);
    for (int i = 0; i < r; i++) {
        for (int j = 0; j < c2; j++){
            int sum = 0;
            for (int k = 0; k < c; k++) {
                sum += arr1[i][k] * arr2[k][j];
            }
            answer[i].push_back(sum);
        }
    }
    return answer;
}