Массивчики

#include<iostream>

using namespace std;


int n;

void swap_cow(int** a)
{
    int rg, lf;
    if (n % 2 == 0)
    {
        rg = n / 2;
        lf = rg - 1;
    }
    else
    {
        rg = n / 2;
        lf = 0;
    }
    for (int i = 0; i < n; ++i)
    {
        int buff = a[i][rg];
        a[i][rg] = a[i][lf];
        a[i][lf] = buff;
    }

}
int main()
{
    cin >> n;
    int** a = new int* [n];
    for (int i = 0; i < n; ++i)
        a[i] = new int[n];
    for (int i = 0; i < n; ++i)
        for (int j = 0; j < n; ++j)
            cin >> a[i][j];
    swap_cow(a);

    for (int i = 0; i < n; ++i)
    {
        for (int j = 0; j < n; ++j)
            cout << a[i][j] << '\t';
        cout << endl;
    }
}