#include <iostream>
using namespace std;

int F[45];

int main() {
	int n;
	cin >> n;
	F[0] = 1;
	F[1] = 1;
	for (int i = 2; i <= n; i++)
		F[i] = F[i - 2] + F[i - 1];
	cout << F[n] << endl;
}
### Prompt

Please provide a cpp coded solution to the problem described below:

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>
using namespace std;

int F[45];

int main() {
	int n;
	cin >> n;
	F[0] = 1;
	F[1] = 1;
	for (int i = 2; i <= n; i++)
		F[i] = F[i - 2] + F[i - 1];
	cout << F[n] << endl;
}
```