My code

… was written in C++11 and can be compiled with G++, Clang++, Visual C++. You can download it, too. Or just jump to my GitHub repository.

The code contains #ifdefs to switch between the original problem and the Hackerrank version.
Enable #ifdef ORIGINAL to produce the result for the original problem (default setting for most problems).

       
#include <iostream>
       
 
       
// I generate a "fingerprint" for each number:
       
// e.g. a fingerprint of 40231 means that the parameter had
       
// 1 zero
       
// 3 ones
       
// 2 threes
       
// no fours
       
// 4 fives
       
// and no sixes, sevens, ...

       
unsigned long long fingerprint(unsigned int x)
       
{
       
  unsigned long long result = 0;
       
 
       
  while (x > 0)
       
  {
       
    // extract right-most digit
       
    auto digit = x % 10;
       
    x /= 10;
       
 
       
    // add 10^digit
       
    unsigned long long pos = 1;
       
    for (unsigned int i = 1; i <= digit; i++)
       
      pos *= 10;
       
    result += pos;
       
  }
       
 
       
  return result;
       
}
       
 
       
int main()
       
{
       
  // the result can be found with 1000000 6
       
  unsigned int maxNumber   = 1000000;
       
  unsigned int maxMultiple = 6;;
       
  std::cin >> maxNumber >> maxMultiple;
       
 
       
  // look at all numbers
       
  for (unsigned int i = 1; i <= maxNumber; i++)
       
  {
       
    // initial fingerprint
       
    auto id = fingerprint(i);
       
 
       
    bool found = true;
       
    for (unsigned int multiple = 2; multiple <= maxMultiple; multiple++)
       
      // mismatch ? => abort
       
      if (id != fingerprint(i * multiple))
       
      {
       
        found = false;
       
        break;
       
      }
       
 
       
    // print result
       
    if (found)
       
    {
       
//#define ORIGINAL

       
#ifdef ORIGINAL
       
      std::cout << i << std::endl;
       
      return 0;
       
#endif
       
 
       
      for (unsigned int multiple = 1; multiple <= maxMultiple; multiple++)
       
        std::cout << (i * multiple) << " ";
       
      std::cout << std::endl;
       
    }
       
  }
       
 
       
  return 0;
       
}

This solution contains 10 empty lines, 16 comments and 3 preprocessor commands.