Untitled

#include <iostream>
using namespace std;
int main()
{
    int a, b;
    cin >> a;
    if (a >= 15)
    {
        a = a / 10;
        b = a - 1;
        a = a * b;
        cout << a << "25";
    }
    else
        a = a * a;
        cout << a;
    return 0;
}