#include <bits/stdc++.h>
using namespace std;

int main(){
    int n;
    cin >> n;
    int dp[n+1];
    dp[0] = 1;
    dp[1] = 1;
    for(int i = 2; i <= n; i++) dp[i] = dp[i-1] + dp[i-2];

    cout << dp[n] << endl;
}

### Prompt

Please formulate 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 <bits/stdc++.h>
using namespace std;

int main(){
    int n;
    cin >> n;
    int dp[n+1];
    dp[0] = 1;
    dp[1] = 1;
    for(int i = 2; i <= n; i++) dp[i] = dp[i-1] + dp[i-2];

    cout << dp[n] << endl;
}

```