#include <cstdio>
#include <cstring>
#include <iostream>
#include <algorithm>
using namespace std;

int a[210][1000];
int len[210];

void sol(int x, int c[], int b[])
{
    int l = max(len[x-1], len[x-2]);
    int j = 0;
    for(int i = 0; i <= l; i++)
    {
        a[x][i] = c[i] + b[i] + j;
        if(a[x][i] > 9)
        {
            j = 1;
            a[x][i] %= 10;
        }
        else
            j = 0;
        //printf("%d ", a[x][i]);
    }
    while(!a[x][l] && l > 0)
        l--;
    l++;
    len[x] = l;
}
int main(int argc, char const *argv[])
{
    memset(a, 0, sizeof(a));
    memset(len, 0, sizeof(len));
    len[1] = 1;
    a[1][0] = 1;
    len[2] = 1;
    a[2][0] = 2;
    for(int i = 3; i <= 200; i++)
        sol(i, a[i-1], a[i-2]);
    int n;
    while(~scanf("%d", &n))
    {
        // printf("%d\n", n);
        for(int i = len[n]-1; i >= 0; i--)
            printf("%d", a[n][i]);
        printf("\n");
    }

    return 0;
}