#include <iostream>

using namespace std;

int f91(int N)
{
    if(N<=100)
    {
        return f91(f91(N+11));
    }
    if(N>=101)
    {
        return N-10;
    }
}

int main()
{
    for(;;)
    {
        int n;
        cin>>n;

        if(n==0)
        {
            break;
        }
        cout<<"f91("<<n<<") = "<<f91(n)<<endl;
    }
    return 0;
}