text: #include "problem.h"
  
  Problem::Problem(FILE *file) : size(0) {
      fscanf(file, "%d", &size);
      fscanf(file, "%s", input);
  }
  
  Problem::Problem(std::minstd_rand &generator, const int length)
      : size(length) {
      for (int i = 0; i < length; i++)
          input[i] = 'a' + (generator() % 26);
      input[length] = '\0';
  }
  
  Problem::Problem(const char *inputStr, const int length)
      : size(length) {
      for (int i = 0; i < length; i++) input[i] = inputStr[i];
  }
  
  