#include<stdio.h>
int main() {
    int limit;
    scanf("%d", &limit);
    if(limit < 0) {
        printf("Input invalid");
        return 0;
    }
    int a = 0, b = 1;
     if (a <= limit)
     printf("%d", a);
     if ( b <= limit)
     printf("%d" , b):
      int next = a + b;
       while ( next <= limit) {
           printf("%d" , next);
           a = b;
            b = next ;
            next = a + b;
       }
       return 0;
}