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SILAMBARASAN A
SILAMBARASAN A

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Prime number

What is prime number?
A number is called a prime number if it has only two factors.

Important Notes
2 is the only even prime number
Numbers less than or equal to 1 are not prime

Flower chart

JAVA Script:

let num = Number(prompt("Enter a number: "));
let div = 2;
let flag = true;

while (div <= num / 2) {
    if (num % div === 0) {
        flag = false;
        break;
    }
    div++;
}

if (flag === true && num > 1) {
    console.log("This number is Prime");
} else {
    console.log("This number is not Prime");
}
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OUTPUT:

PYTHON:

num=int(input("enter a number: "))
div=2
flag=True
while div<=num/2:
    if num%div==0:
        flag=False
        break
    div+=1
if flag==True:
    print("This number is Prime")
else:
    print("This number is not Prime")
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OUTPUT:

JAVA:

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {

        Scanner sc = new Scanner(System.in);
        System.out.print("Enter a number: ");
        int num = sc.nextInt();

        boolean flag = true;

        if (num <= 1) {
            flag = false;
        } else {
            for (int i = 2; i <= Math.sqrt(num); i++) {
                if (num % i == 0) {
                    flag = false;
                    break;
                }
            }
        }

        if (flag) {
            System.out.println("This number is Prime");
        } else {
            System.out.println("This number is not Prime");
        }

        sc.close();
    }
}
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OUTPUT:

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