Java Program to print first “n” Numbers in Fibonacci Series
Write a Java Program to display first “n” numbers in the Fibonacci series.
Fibonacci series: 0, 1, 1, 2, 3, 5, 8, 13 and so on
If the value of n is 5, then the expected output is 0, 1, 1, 2, 3
Logic is: f1 = 0, f2 = 1, f3 = f1 + f2
Video Tutorial:
Steps (Program logic):
1. Declare variables like n, f1, f2, f3.
2. Create an object of Scanner class to read the input from standard keyboard.
3. Check the value of n , if the value of n is 1 display f1 that is 0.
4. If the value of n is 2, display f1 and f2 that is 0 and 1.
5. If the value of n is greater than 2 then display f1, f2 and calculate the next number in the series using formula f3=f1+f2.
6. if the value of n is less than or equal 0 then display that the error message like invalid input.
Source code of Java Program to print first “n” Numbers in Fibonacci Series
import java.util.Scanner;
/*
Write a Java Program to display first "n" numbers in Fibonacci series
Subscribe to Mahesh Huddar YouTube Channel for more Videos
Fibonacci series: 0, 1, 1, 2, 3, 5, 8, 13 and so on
Logic: f1 = 0, f2 = 1, f3 = f1 + f2
*/
public class Fibonacci
{
public static void main(String args[])
{
int n, f1 = 0, f2 = 1, f3;
Scanner input = new Scanner(System.in);
System.out.print("Enter the value of n:");
n = input.nextInt();
System.out.print("Fibonacci series is: ");
if (n == 1)
{
System.out.print(f1);
}
else if (n == 2)
{
System.out.print(f1 +" "+ f2);
}
else if (n > 2)
{
System.out.print(f1 +" "+ f2+" ");
for (int i = 3; i<=n; i++)
{
f3 = f1 + f2;
System.out.print(f3+" ");
f1 = f2;
f2 = f3;
}
}
else
{
System.out.print("Invalid Input - Enter the value of n greater than 0");
}
}
} Output:
Case 1:
Enter the value of n: 1
Fibonacci series is: 0
Case 2:
Enter the value of n: 2
Fibonacci series is: 0 1
Case 3:
Enter the value of n: 5
Fibonacci series is: 0 1 1 2 3
Case 4:
Enter the value of n: -10
Fibonacci series is: Invalid Input – Enter the value of n greater than 0
If you like the tutorial share it with your friends. Like the Facebook page for regular updates and YouTube channel for video tutorials.