Answer to Question #43475 in C++ for dharshana

Question

write a function to check whether the number entered by a user is a prime number

Answer 1

#include <iostream>
bool isPrime(int n) {
    if ( n <= 1 ) {
        return false;
    }
    for ( int i = 2; i <= n / 2; i++ ) {
        if ( n % i == 0 ) {
            return false;
        }
    }
    
    return true;
}
int main() {
    int number, input;
    while ( true ) {
        std::cout << "Please enter the number to be checked for being prime" << std::endl;
        std::cin >> number;
        
        if ( isPrime(number) )  {
            std::cout << "Prime" <<std::endl;
        } else  {
            std::cout << "Not prime" << std::endl;
        }
        std::cout << "Another check? 0 for no" << std::endl;
        std::cin >> input;
        if (! input ) {
            break;
        }
    }
}