/* 
 * File:   main.cpp
 * Author: semprathlon
 *
 * Created on May 15, 2016, 1:16 PM
 */

#include <cstdio>
#include <cstdlib>
#include <iostream>
#include <cmath>

using namespace std;

typedef long long ll;

const int maxn = 210;

struct BigInt {
    const static int mod = 10000;
    const static int DLEN = 4;
    int a[20], len;

    BigInt() {
        memset(a, 0, sizeof (a));
        len = 1;
    }

    BigInt(int v) {
        memset(a, 0, sizeof (a));
        len = 0;
        do {
            a[len++] = v % mod;
            v /= mod;
        } while (v);
    }

    BigInt(const char s[]) {
        memset(a, 0, sizeof (a));
        int L = strlen(s);
        len = L / DLEN;
        if (L % DLEN)len++;
        int index = 0;
        for (int i = L - 1; i >= 0; i -= DLEN) {
            int t = 0;
            int k = i - DLEN + 1;
            if (k < 0)k = 0;
            for (int j = k; j <= i; j++)
                t = t * 10 + s[j] - '0';
            a[index++] = t;
        }
    }

    BigInt operator+(const BigInt & b)const {
        BigInt res;
        res.len = max(len, b.len);
        for (int i = 0; i <= res.len; i++)
            res.a[i] = 0;
        for (int i = 0; i < res.len; i++) {
            res.a[i] += ((i < len) ? a[i] : 0)+((i < b.len) ? b.a[i] : 0);
            res.a[i + 1] += res.a[i] / mod;
            res.a[i] %= mod;
        }
        if (res.a[res.len] > 0)res.len++;
        return res;
    }

    BigInt operator*(const BigInt & b)const {
        BigInt res;
        for (int i = 0; i < len; i++) {
            int up = 0;
            for (int j = 0; j < b.len; j++) {
                int temp = a[i] * b.a[j] + res.a[i + j] + up;
                res.a[i + j] = temp % mod;
                up = temp / mod;
            }
            if (up != 0)
                res.a[i + b.len] = up;
        }
        res.len = len + b.len;
        while (res.a[res.len - 1] == 0 && res.len > 1)res.len--;
        return res;
    }

    void output() {
        printf("%d", a[len - 1]);
        for (int i = len - 2; i >= 0; i--)
            printf("%04d", a[i]);
//        printf("\n");
    }
} f[maxn];

void get() {
    f[0]=1;f[1]=1;
    for(int i=2;i<maxn;i++)
        f[i]=f[i-2]+f[i-1];
}

int main(int argc, char** argv) {
    get();
    int n;
    while (~scanf("%d", &n)) {
        f[n].output();cout<<endl;
    }
    return 0;
}