Fibonacci Java

Question

• You are given a number n.
• You are required to print the nth element of the Fibonacci sequence.

Note -> Notice precisely how we have defined the Fibonacci sequence

0th element -> 0
1st element -> 1
2nd element -> 1
3rd element -> 2
4th element -> 3
5th element -> 5
6th element -> 8

Input Format

A number n

Constraints

0 <= n <= 45

Sample Input

10

Sample Output

55

Program

import java.io.*;
import java.util.*;

public class Main {

    public static void main(String[] args) throws Exception {
        // write your code here
        Scanner scn = new Scanner(System.in);
        int n = scn.nextInt();
        int ans = fib(n, new int[n + 1]);
        System.out.println(ans);
    }
    
    public static int fib(int n, int[] qb){
        if(n == 0 || n == 1){
            return n;
        }
        if(qb[n] != 0){
            return qb[n];
        }
        
        int fib1 = fib(n - 1, qb);
        int fib2 = fib(n - 2, qb);
        int fibs = fib1 + fib2;
        
        qb[n] = fibs;
        return fibs;
    }

}