Java Program tutorials to check Prime nos

Example: program to enter a no and print it is Prime number or not.

// program name Main052.java

// program to enter a no and print it is Prime number or not.

import java.util.Scanner;

public class Main0

{

public static void main(String[] args)

{

int no, i;

System.out.print("Enter an integer : ");

Scanner scan=new Scanner(System.in);

no=scan.nextInt();

int limit;

limit= (int) Math.sqrt(no);

i = 2;

while(no%i != 0 && i <= limit)

i++;

if(i > limit)

System.out.printf("%d is Prime Number",no);

else

System.out.printf("%d is Not Prime Number",no);

}

}

Output

Enter an integer : 125

125 is Not Prime Number

Enter an integer : 17

17 is Prime Number

Example: program to enter a no and print it is Prime number or not.

// program name Main052New.java

// program to enter a no and print it is Prime number or not.

import java.util.Scanner;

public class Main0

{

public static void main(String[] args)

{

int n,i,f=0;

Scanner scan=new Scanner(System.in);

System.out.println("Enter a value: ");

n=scan.nextInt();

for(i=1;i<=n;i++)

{

if(n%i==0)

f++;

}

if(f==2)

{

System.out.println(n+" is a prime number");

}

else

{

System.out.println(n+" is not a prime number");

}

}

}

Output

Enter a value : 1

1is not a prime number

Enter a value : 3

3 is a prime number