check prime no. in C++

 #include <iostream>

using namespace std;

int main(){

    int n = 7;

    bool isPrime = true; // assumes all numbers are prime

    for(int i = 2; i <= n-1; i++){

        if(n % i == 0){ // i is a factor of n; i completely divides n; n is non-prime

            isPrime = false;

            break;

        }

    }

   

    if(isPrime){ // or if(isPrime == true)

        cout << "number is prime " << endl;

    } else{

        cout << "number is not prime" << endl;

    }

   

    return 0;

}