#include<iostream>
using namespace std;
int main(){
    int limit;
    if(!(cin>>limit)){
        cout<<"invalid input\n";
        return 0;
    }
    if(limit<0){
        cout<<"0\n";
        return 0;
    }
    int a=0;
    int b=1;
    cout<<a;
    while(b<=limit){
        cout<<""<<b;
        intc=a+b;
        a=b;
        b=c;
    }
    cout<<"\n";
    return 0;
}