#include <iostream>
#include<string>
#include<cstring>
#include<vector>
#include<set>
#include<stack>
#include<queue>
#include<list>
#include<cmath>
#include<algorithm>
#include<cstdio>
#include<map>
#include<iomanip>
#define INF 0x3f3f3f
using namespace std;
#define ll long long

string sum(string num1,string num2){
    if(num1.size()<num2.size()){
        string temp=num1;
        num1=num2;
        num2=temp;
    }
    int length1=num1.size(),length2=num2.size(),flag=0,a,b,sum;
    while(length1>0){
        a=num1[length1-1]-'0';
        if(length2>0)
            b=num2[length2-1]-'0';
        else
            b=0;
        sum=a+b+flag;
        if(sum>=10){
            num1[length1-1]='0'+sum%10;
            flag=1;
        }else{
            num1[length1-1]='0'+sum;
            flag=0;
        }
        length1--;
        length2--;
    }
    if(1==flag)
        num1="1"+num1;
    return num1;
}
string Num[200+20];
int main()
{
    Num[1]="1";
    Num[2]="2";
    for(int i=3;i<200+10;i++)
    {
        Num[i]=sum(Num[i-1],Num[i-2]);
    }
    int N;
    while(cin>>N)
    {
        cout<<Num[N]<<endl;
    }
    return 0;
}