#include<iostream>
#include<stdio.h>
using namespace std;
int main()
{
	int i=0,n,dp[45]={0};
	cin>>n;
	dp[0]=1;
	dp[1]=1;
	while(dp[n]<=0)
	{
		dp[i+2]=dp[i]+dp[i+1];
		i++;
	}
	cout<<dp[n]<<endl;	
	return 0;
}
### Prompt

Construct a CPP code solution to the problem outlined:

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<stdio.h>
using namespace std;
int main()
{
	int i=0,n,dp[45]={0};
	cin>>n;
	dp[0]=1;
	dp[1]=1;
	while(dp[n]<=0)
	{
		dp[i+2]=dp[i]+dp[i+1];
		i++;
	}
	cout<<dp[n]<<endl;	
	return 0;
}
```