f91

//  G - Guess the function, you geek!
//  Date : 11.05.19
#include<iostream>
#include<cstdio>
using namespace std;

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

int main(){
    int n;
    while(scanf("%d", &n) == 1 && n != 0){
        if(n <= 101)printf("f91(%d) = %d\n", n,91);
        else printf("f91(%d) = %d\n", n,n-10);
    }
}