#include<iostream>
#include<cstdio>
using namespace std;
typedef long long int ll;
ll Dp[50];
int main()
{
Dp[0]=1;
Dp[1]=1;
for(int i=2;i<50;i++)Dp[i]=Dp[i-1]+Dp[i-2];
int N;
cin >> N;
cout << Dp[N] << "\n";
 
return 0;
}
### Prompt

Your task is to create a Cpp solution to the following problem:

Write a program which prints $n$-th fibonacci number for a given integer $n$. The $n$-th fibonacci number is defined by the following recursive formula:

\begin{equation*} fib(n)= \left \\{ \begin{array}{ll} 1 & (n = 0) \\\ 1 & (n = 1) \\\ fib(n - 1) + fib(n - 2) & \\\ \end{array} \right. \end{equation*}

Constraints

* $0 \leq n \leq 44$

Input

An integer $n$ is given.

Example

Input

3


Output

3

### Response

```cpp
#include<iostream>
#include<cstdio>
using namespace std;
typedef long long int ll;
ll Dp[50];
int main()
{
Dp[0]=1;
Dp[1]=1;
for(int i=2;i<50;i++)Dp[i]=Dp[i-1]+Dp[i-2];
int N;
cin >> N;
cout << Dp[N] << "\n";
 
return 0;
}
```