TestsPrimality

A Function that TestsPrimality

bool isPrime( unsigned int n )
{ // returns true if n is prime, false otherwise:
    if( n < 2 ) 
        return false; // 0 and 1 are not primes

    if( n < 4 ) 
        return true; // 2 and 3 are the first primes

    if( n%2 == 0 ) 
        return false; // 2 is the only even prime

    float sqrtn = sqrt( n ); // pasar a (unsigned int) para no comparar "integer <= float" en el for
    for( int d = 3; d <= sqrtn; d += 2 )
        if( n%d == 0 ) 
            return false; // n has a nontrivial divisor
    
    return true; // n has no nontrivial divisors
}