What is Fibonacci series?
- Fibonacci number is obtained by adding two preceding numbers.
- Fibonacci series is collection of fibonacci numbers.
- e.g. fibonacci series is 0, 1, 1, 2, 3, 5
- next number is fibonacci series is 3 + 5 = 8
- fibonacci series becomes 0, 1, 1, 2, 3, 5, 8
- next number is fibonacci series is 5 + 8 = 13
- fibonacci series becomes 0, 1, 1, 2, 3, 5, 8, 13
- Fibonacci series is named after Italian mathematician Leonardo of Pisa, known as Fibonacci.
- Fibonacci numbers is defined by the recurrence relation:
- F(n) = F(n-1) + F(n-2) where F0 = 0 & F1 = 1.
Generate fibonacci numbers in java – recursive algorithm:
- We have shown recursive algorithm to find fibonacci number.
- There are couple of flavors of fibonacci service
- 1 1 2 3 5 8 13 21 34 55
- 0 1 1 2 3 5 8 13 21 34 55 (with o at first number)
- We have demonstrated point 2 in this post.
- We have calculate the fibonacci number for input = 4.
- recursive(4) = 3 (refer Fig 1).
Program: print fibonacci series in java (recursive & iterative algorithm)
package org.learn;import java.util.Scanner;public class FibonacciSeries { private static int fibRecursive(int number) { if (number == 0 || number == 1) return number; int fibNumber = fibRecursive(number - 1) + fibRecursive(number - 2); return fibNumber; } private static void fibIterative(int number) { int prev = 0, curr = 1; System.out.printf("%d %d ",prev,curr); int fibNumber = 0; for (int series = 2; series < number; series++) { fibNumber = prev + curr; prev = curr; curr = fibNumber; System.out.printf("%d ",fibNumber); } return; } public static void main(String[] args) { try (Scanner scanner = new Scanner(System.in)) { System.out.print("1.) Enter input number : "); int inputNumber = scanner.nextInt(); System.out.print("2.) Fibonacci series using Recursive method: "); for (int number = 0; number < inputNumber; number++) { //it can be optimized, for simplicity we are invoking for each number System.out.printf("%d ", fibRecursive(number)); } System.out.print("\n3.) Fibonacci series using iterative method: "); fibIterative(inputNumber); } }} |
Output: print Fibonacci series in java using recursive algorithm
1. Enter input number : 52. Fibonacci series using Recursive method: 0 1 1 2 3 3. Fibonacci series using iterative method: 0 1 1 2 3 1. Enter input number : 102. Fibonacci series using Recursive method: 0 1 1 2 3 5 8 13 21 34 3. Fibonacci series using iterative method: 0 1 1 2 3 5 8 13 21 34 |