Write a Java program to input a number and check if it is prime or not

 

Write a program  in Java to input a number and check if it is  prime or not

Prime Number : A number that is divisible only by itself and 1 (e.g. 2, 3, 5, 7, 11).

import java.util.Scanner;

public class Prime {

public static void main(String[] args) {

Scanner sc = new Scanner(System.in);

System.out.print("Enter A Positive Number : ");

int num=sc.nextInt();

sc.close();

boolean isPrime=true;

if (num==1) {

System.out.print(" 1 Is Unitary");

} else if(num==2) {

System.out.print(" 2 Is Prime Number");

}else {

for (int i = 2; i < num/2; i++) {

if (num%i==0) {

isPrime=false;

break;

}

}

if (isPrime) {

System.out.print(num +" Is Prime Number");

} else {

System.out.print(num +" Is Not Prime Number");

}

}

}

}

OUTPUT

1.

   Enter A Positive Number : 45

   45 Is Not Prime Number

2.

   Enter A Positive Number : 47

   47 Is Prime Number

Program 2

Read More

Write a Java program to input a number and check if it is palindrome or not

 Write a program  in Java to input a number and check if it is  palindrome or not

Palindrome : A palindrome is a word, number, phrase, or other sequence of characters which reads the same backward as forward, such as madam or racecar.

import java.util.Scanner;

public class Palin {

public static void main(String[] args) {

Scanner sc =new Scanner(System.in);

System.out.print("Enter A Number : ");

int num =sc.nextInt();

int rev=0,ldigit;

int temp=num;

while (temp!=0) {

ldigit=temp%10;

rev=rev*10+ldigit;

temp=temp/10;

}

if (num==rev) {

System.out.println(num +" is Palindrome");

} else {

System.out.println(num +" is not Palindrome");

}

}

}

 

OUTPUT

1. 

     Enter a Number : 123454321

     123454321 is Palindrome

2. 

     Enter a Number : 345232

     345232 is not Palindrome

Read More