write a computer java program to find whether number is prime or not
Answers
Answer:
Prime Number Program in Java
public class PrimeExample{
public static void main(String args[]){
int i,m=0,flag=0;
int n=3;//it is the number to be checked.
m=n/2;
if(n==0||n==1){
System.out.println(n+" is not prime number");
}else{
import java.util.Scanner;
class PrimeCheck
{
public static void main(String args[])
{
int temp;
boolean isPrime=true;
Scanner scan= new Scanner(System.in);
System.out.println("Enter any number:");
//capture the input in an integer
int num=scan.nextInt();
scan.close();
for(int i=2;i<=num/2;i++)
{
temp=num%i;
if(temp==0)
{
isPrime=false;
break;
}
}
//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
19 is a Prime Number
Output 2:
Enter any number:
6
6 is not a Prime Number
You can also use while loop to check the prime number:
Just replace this part of the code in above program:
for(int i=2;i<=num/2;i++)
{
temp=num%i;
if(temp==0)
{
isPrime=false;
break;
}
}
with this:
int i=2;
while(i<= num/2)
{
if(num % i == 0)
{
isPrime = false;
break;
}
i++;
}