题解 | #矩阵乘法#

#include <iostream>
#include <vector>
#include <bits/stdc++.h>
using namespace std;

int main() {
    int x,y,z;
    cin>>x>>y>>z;
    int num;
    int res = 0;
    vector<vector<int>> v1(x,vector<int>(y,0));
    vector<vector<int>> v2(y,vector<int>(z,0));
    vector<vector<int>> v3(x,vector<int>(z,0));
    for(int i =0;i<x;i++){
        for(int j=0;j<y;j++){
            cin>>num;
            v1[i][j] = num;
        }
    }
    for(int i =0;i<y;i++){
        for(int j=0;j<z;j++){
            cin>>num;
            v2[i][j] = num;
        }
    }
    

    for(int i =0;i<x;i++){
        for(int j=0;j<z;j++){
            res = 0;
            for(int a=0;a<y;a++){
                res = res+ v1[i][a]*v2[a][j];
            }
            v3[i][j] = res;
           
        }
    }
    for(int i =0;i<x;i++){
        for(int j=0;j<z;j++){
            cout<<v3[i][j]<<" ";
        }
        cout<<endl;
    }

}
// 64 位输出请用 printf("%lld")