1 #include <iostream>
 2 #include <cstdio>
 3 #include <cstring>
 4 #include <cmath>
 5 using namespace std;
 6 int d[40]={0,1};
 7 int main()
 8 {
 9     int i,j;
10     for(i=2;i<=20;i++)
11     d[i]=d[i-1]+d[i-2];
12     int n,ans;
13     double p,f;
14     f=(1.0+sqrt(5.0))/2.0;
15     while(~scanf("%d",&n))
16     {
17         if(n<21)
18         {
19             printf("%d\n",d[n]);
20             continue;
21         }
22         p=-0.5*log10(5.0)+n*1.0*log(f)/log(10.0);
23         p=p-(int)p;
24         p=pow(10.0,p);
25         while(p<1000)
26         p*=10;
27         printf("%d\n",(int)p);
28     }
29     return 0;
30 }