#include <cstdio>
#include <cstring>
#include <cmath>
#include <string>
#include <iostream>
#include <algorithm>
using namespace std;
#define INF 0x3f3f3f3f
#define eps 1e-8
typedef long long LL;

class Bign
{
public:
    int len, s[200];
    Bign()
    {
        memset(s,0,sizeof(s));
        len = 1;
    }
    
    string str() const
    {
        string res = "";
        for (int i = 1; i <= len; i++)
            res = (char)(s[i]+'0') + res;
        if (res == "") res = "0";
        return res;
    }
    
    Bign operator = (const int &n)
    {
        memset(s, 0, sizeof(s));
        int k = n; len = 0;
        while (k)
        {
            len++;
            s[len] = k % 10;
            k /= 10;
        }
        if (!len) len++;
        return *this;
    }
    Bign (const string n) {*this = n;}
    Bign (const int n) {*this = n;}

    Bign operator + (const Bign &a) const
    {
        Bign c;
        c.len = max(len, a.len) + 1;
        for (int i = 1, g = 0; i <= c.len; i++)
        {
            int x = s[i] + a.s[i] + g;
            c.s[i] = x % 10;
            g = x / 10;
        }
        while (!c.s[c.len] && c.len > 1) c.len--;
        return c;
    }
    Bign operator += (const Bign &a)
    {
        *this = *this + a;
        return *this;
    }
};

istream& operator >> (istream &in, Bign &x)
{
    string s;
    in >> s;
    x = s;
    return in;
}

ostream& operator << (ostream &out, const Bign &x)
{
    out << x.str();
    return out;
}

Bign f[205];
int n;

int main()
{
    memset(f, 0, sizeof(f));
    f[0] = f[1] = 1;
    for (int i = 2; i <= 200; i++)
        f[i] = f[i-1] + f[i-2];
    while (scanf("%d", &n) != EOF)
        cout << f[n] << "\n";
    return 0;
}