Problem:
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Fibonacci Number

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*}

Input

An integer $n$ is given.

output

Print the $n$-th fibonacci number in a line.

Constraints

$0 \leq n \leq 44$

Sample Input 1

3

Sample Output 1

3

Solution in JAVA (judge verdict: Accepted)

import java.util.*;

public class Main{
	public static void main(String[] args){
		Scanner scan = new Scanner(System.in);

		int n = scan.nextInt();
		long[] f = new long[n+1];

		System.out.println(Fib(n, f));

		scan.close();
		System.exit(0);
	}

	private static long Fib(int n, long[] f){
		if(n <= 1)
			return 1;
		if(f[n] != 0)
			return f[n];
		f[n] = Fib(n-2, f) + Fib(n-1, f);
		return f[n];
	}
}