#include <iostream>

using namespace std;

int main()
{
    double x,f;
    cout<<"x= ";
    cin>>x;
    if(x<=-3)
    {
        f=x*x+1;
        cout<<"f= "<<f<<endl;
    }
    if(x>-3&&x<3)
    {
        f=x-2;
        cout<<"f= "<<f<<endl;
    }
    if(x>=3)
    {
        f=x*x-4*x+5;
        cout<<"f= "<<f<<endl;

    }
    return 0;
}