java code to check is number is prime code example

Example 1: program to know if a number is prime

#include<bits/stdc++.h>
using namespace std;
bool Is_Prime(long long x){
	if(x%2==0)return false;
	for(int i=3;i*i<=x;i+=2)
		if(x%i==0)return false;
	return true;
}
int main(){
	long long x;
	cin>>x;
	if(Is_Prime(x))cout<<"Is Prime";
	else cout<<"Is not Prime";
}

Example 2: how to check if number prime in java

public class PrimeNumberInJava
{
   public static void main(String[] args)
   {
      int a, b = 0, flag = 0;
      int number = 66;
      b = number / 2;
      if(number == 0 || number == 1)
      {
         System.out.println(number + " is not prime number");
      }
      else
      {
         for(a = 2; a <= b; a++)
         {
            if(number % a == 0)
            {
               System.out.println(number + " is not prime number.");
               flag = 1;
               break;
            }
         }
         if(flag == 0)
         {
            System.out.println(number + " is prime number.");
         }
      }
   }
}