swap for chetverty

#include <iostream>
#include<iomanip>
#include<ctime>
using namespace std;
void main()
{
    srand(time(NULL));
    const int n = 5;
    int mas[n][n];
    for (int i = 0; i < n; i++)
    {
        for (int j = 0; j < n; j++)
            mas[i][j] = rand() % 9 +1;
    }
    cout << "Source array:" << endl;
    for (int i = 0; i < n; i++)
    {
        for (int j = 0; j < n; j++)
            cout << setw(4) << mas[i][j];
        cout << endl;
    }
    for (int i = 0; i<n/2; i++)
        for (int j = 0; j < n/2; j++)
        {
            if(n==n%2)swap(mas[i][j],mas[n / 2 + i][n / 2 + j]);
            else {
                swap(mas[i][j], mas[n - 1 - i][n - 1 - j]);
                //int tmp = mas[i][i];mas[i][i] = mas[n - 1 - i][n - 1 - i];mas[n - 1 - i][n - 1 - i] = tmp;
            }
        }
    cout << "Result array:" << endl;
    for (int i = 0; i < n; i++)
    {
        for (int j = 0; j < n; j++)
            cout << setw(4) << mas[i][j];
        cout << endl;
    }
    system("pause");
}