#include<iostream>
using namespace std;

    int main(){
        int limit;
        cin>>limit;
        
        if (limit<0){
            cout<<a<<"inva;id input";
            return 0;
        }
        int a=0,b=1;
        while (a<= limit){
            cout <<a<<"";
            int next = a+b;
            a=b;
            b=next;

        }
        return 0
}