In this java program tutorial, we will write a java program to display the Fibonacci series. Let us first understand what is Fibonacci series is and then the Java program to generate them.
What is Fibonacci Series?
Fibonacci series is the series of numbers where the next number is achieved by the addition of the previous two numbers. The initial addition of two numbers is 0 and 1.
For example: 0,1,1,2,3,5,8,13….etc.
We will see two ways to print the Fibonacci Series.
- With the help of iteration(for-loop).
- Using recursion.
Program Explanation:
First, we need to initialize the two terms as 0 and 1 as a = 0, b = 0; then get user input for the total number of elements in a series which is stored in an integer variable n.
After that start iteration up to the number of elements the user inputs. Inside for loop, we assigned the b value in a and the sum value in b and the sum is the addition of a and b. Then we print the value at every iteration as shown in a program.
At last, the program exits the iteration when integer i is less than or equal to the number of elements as,i <= n.
1. Java program to display Fibonacci series using for loop
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 | //Fibonacci series in java import java.util.Scanner; public class FibonacciJava { public static void main(String[] args) { int n, a = 0, b = 0, sum = 1; Scanner s = new Scanner(System.in); System.out.print("Enter the Number:"); n = s.nextInt(); System.out.print("Fibonacci Series of entered number are:"); for (int i = 1; i <= n; i++) //display { a = b; b = sum; sum = a + b; System.out.print(a + " "); } } } |
Output:
Enter the Number:6
Fibonacci Series of entered number are:0 1 1 2 3 5
2. Fibonacci series using Recursion in java
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 | //Fibonacci Using Recursion import java.util.Scanner; public class FiboSeries { public static int fiboRecursion(int n) { if(n == 0) { return 0; } if(n == 1 || n == 2) { return 1; } return fiboRecursion(n-2) + fiboRecursion(n-1); } public static void main(String args[]) { int number; Scanner s = new Scanner(System.in); System.out.print("Enter the Number:"); number = s.nextInt(); System.out.print("Fibonacci Series of entered number: "); for(int i = 0; i < number; i++) { System.out.print(fiboRecursion(i) +" "); } } } |
After executing, the following output will be obtained.
Enter the Number:8
Fibonacci Series of entered number: 0 1 1 2 3 5 8 13