矩阵行成列，列成行

#include<iostream>
#include<vector>
using namespace std;
int main()
{
    vector<vector<int>> vet;
    for (int i = 0; i < 3; i++)
    {
        vector<int> vet1;
        for (int j = 0; j < 3; j++)
        {
            int x;
            cin >> x;
            vet1.push_back(x);
        }
        vet.push_back(vet1);
    }
    for (int i = 0; i < 3; i++)
    {
        for (int j = 0; j < 3; j++)
        {
            cout << vet[i][j] << " ";
        }
        cout << endl;
    }
    vector<vector<int>> cp;
    cp = vet;
    for (int i = 0; i < 3; i++)
    {
        for (int j = 0; j < 3; j++)
        {
            vet[i][j] = cp[j][i];
        }
    }
    for (int i = 0; i < 3; i++)
    {
        for (int j = 0; j < 3; j++)
        {
            cout << vet[i][j] << " ";
        }
        cout << endl;
    }
    system("pause");
    return 0;
}