Function isPrime

Exercises/NoModules/Chapter 08/Soln8_05.cpp:55–70

The sqrt() in the for loop below is not required. The following loop would be equally correct, just a bit slower: for (unsigned i = 2; i < number; ++i) { ... } It is a quite common optimisation though to stop testing at the square root of the number. Think about why this is correct! */

  the square root of the number. Think about why this is correct!
*/
bool isPrime(unsigned number)
{
  // a prime number is a natural number strictly greater than 1...
  if (number <= 1) return false;
  
  // ...and with no positive divisors other than 1 and itself
  for (unsigned i{ 2 }; i < std::sqrt(number); ++i)
  {
    if (number % i == 0)
    {
      return false;
    }
  }
  
  return true;
}

std::vector<unsigned> generateNumbers(unsigned to, unsigned from)
{