text: #include <string>
  
  #include "format.h"
  
  using std::string;
  
  // TODO: Complete this helper function
  // INPUT: Long int measuring seconds
  // OUTPUT: HH:MM:SS
  // REMOVE: [[maybe_unused]] once you define the function
  string Format::ElapsedTime(long seconds) { 
    int hours = seconds / (60 * 60); 
    seconds = seconds - hours * 60 * 60; 
    int minutes = seconds / 60; 
    seconds = seconds - minutes * 60; 
    
    string time = Format::FillLeadingZero(std::to_string(hours)) + ":" + 
      Format::FillLeadingZero(std::to_string(minutes)) + ":" + 
      Format::FillLeadingZero(std::to_string(seconds)); 
    return time; 
  }
  
  string Format::FillLeadingZero(string in) {
      string out = in; 
  	if (in.size() < 2) { 
        out = "0" + in; 
      } 
      return out; 
  }