#include <stdio.h>
int main()
{
    int limit;
    scanf("%d", &limit);
    
    if(limit < 0) {
        printf("Invalid input\n");
        return 0;
    }
    
    int a = 0, b = 1;
    while (a <= limit){
    printf("%d", a);
    a = b;
    b = next;
}
return 0; 
}