cppstudio_01_02

#include <iostream>
using namespace std;
int main()
{
    //my
    /**
    int a, b, f, x;
    cin >> a >> b >> f;
    x = (a+b-f/a)+f*a*a-(a+b);
    cout << x;
    return 0;
    **/

    //de wey
    int a, b, f, x;
    cin>>a;
    cin>>b;
    cin>>f;
    x=(a + b - f / a) + f * a * a - (a + b);
    cout << x << endl;
}