#include <cstdio>#include <iostream>using namespace std;#ifdef ONLINE_JUDGE                                   #define FINPUT(file)  0#define FOUTPUT(file) 0#else                                                #define FINPUT(file)  freopen(file,"r",stdin)#define FOUTPUT(file) freopen(file,"w",stdout)#endifint main(){    FINPUT("in.txt");    FOUTPUT("out.txt");        int n;    while(cin>>n && n)    {		long long int f1 = 1;		long long int f2 = 2;		long long int f3 = 3;		int i = 4;		while(i<=n)		{			f1 = f2;			f2 = f3;			f3 = f1+f2;						i++; 		} 		if(n==1)			cout<<f1<<endl;		else if(n==2)			cout<<f2<<endl;		else if(n>=3)			cout<<f3<<endl;    }    return 0;}