#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);
     int next = a + b;
     a = b;
     b = next;
 }
   return 0;
}