#include<stdio.h>
int main(){
    int limit,a=0,b=0,c;
    scanf("%d",&limit);
    if(limit<0){
        printf("Invalid input");
    }
    else{
        printf("%d",a);
        while(b<=limit){
            printf("%d",b);
            c=a+b;
            a=b;
            b=c;
        }
    }
    return 0;
}