Java Program To Check Prime Number using While Loop
In this java program, we check whether the user input number is prime or not.
A prime number is a natural number greater than 1 that is not a product of two small natural numbers.
E.g. 2, 3, 5 etc are prime numbers.
Steps :
Step 1 : Import Scanner class
Step 2 : Create class PrimeChec
Step 3 : Create main method
Step 4 : Create variable temp
Step 5 : Create object of Scanner
Step 6 : Ask the user to enter any number by using System.out.print method
Step 7 : Create variable num and store the user entered number in it.
Step 8 : Close the Scanner class
Step 9 : Initialize int i equals to 2
Step 10 : Apply while loop where i is smaller than equal to num divide by 2
Step 11 : Apply if where num mod i is equals equals to zero
Step 12 : Initialize isPrime to False
Step 13 : If isPrime is true then the number is prime else not
Step 14 : Print the number
Program :
import java.util.Scanner;
public class PrimeChecWhile
{
public static void main(String[] args)
{
int temp;
boolean isPrime = true;
Scanner sc = new Scanner(System.in);
System.out.println("Enter any number:");
//capture the input in an integer
int num = sc.nextInt();
sc.close();
int i = 2;
while(i<=num/2)
{
if(num%i==0)
{
isPrime = false;
break;
}
i++;
}
//If isPrime is true then the number is prime else not
if(isPrime)
System.out.println(num+"is a Prime Number");
else
System.out.println(num+"is not a Prime Number");
}
}
Output :
Enter any number:
19
19is a Prime Number
For execution of the same do visit my YouTube Channel :
https://youtu.be/jYxikmPpNb4
