function to check prime number c++ code example

Example 1: c++ find prime numbers

#include <iostream>
using namespace std;

int main()
{
  int n, i;
  bool isPrime = true;

  cout << "Enter a positive integer: ";
  cin >> n;

  for(i = 2; i <= n / 2; ++i)
  {
      if(n % i == 0)
      {
          isPrime = false;
          break;
      }
  }
  if (isPrime)
      cout << "This is a prime number";
  else
      cout << "This is not a prime number";

  return 0;
}

Example 2: check prime in c++

#include <bits/stdc++.h>
using namespace std;

#define ll long long
bool isPrime(ll number){
	  for(ll i = 2; i <= number / 2; i++){
	  
  
      	if(number % i == 0)
      {
          return false;
          break;
      }
 	}
 	
 	return true;
}