Answer to Question #302711 in Java | JSP | JSF for kmr

Question

The Fibonacci sequence is constructed by adding the last two numbers of the sequence so far to get the next number in the sequence. The first and the second numbers of the sequence are defined as 0 and 1. We get:

0, 1, 1, 2, 3, 5, 8, 13, 21…

 

Write a function which takes input as a number:

• If the given number is a Fibonacci number, print the number
• If the given number is NOT a Fibonacci number, print the sum of all odd Fibonacci numbers less than the given number.

Answer 1

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int n = in.nextInt();
        if (n == 0 || n == 1) {
            System.out.println(n);
        } else {
            int answer = 2;
            int first = 1;
            int second = 1;
            while (first + second <= n) {
                if (first + second == n) {
                    answer = n;
                    break;
                }
                if ((first + second) % 2 != 0) {
                    answer += (first + second);
                }
                int tmp = second;
                second += first;
                first = tmp;
            }
            System.out.println(answer);
        }
    }
}