pair<int,int> proccessCoordinate(int pos){
   return hashmap[pos];
  ["0"] = {0,0}
  unordered_map<int,pair<int,int>> hashmap;
  
}
int minimumNumberOfMove(int start,int end){ 
if (start == end){
    return 0;
}
int startX = proccessCoordinate(start).first; 
int startY = proccessCoordinate(start).second; 

int endX = proccessCoordinate(end).first; 
int endY = proccessCoordinate(end).second;


// if they in same color

if ((startX + startY) % 2 != (endX + endY) % 2 ){ 
    return -1;
}

// if they in same diagonal

if (abs(startX - startY) == abs(endX - endY)) { 
    return 1; 
}
return 2;  
}

======= ad.h ============
  
// An ad represents a text ad shown on a web site.
class Ad {    
  
  public:
    Ad(string adText, string keyword, int bid, Account& account) : 
      adText_(std::move(adText)), keyword_(keyword),bid_(bid),account_(account)
    {}
  
    // A user has clicked on this ad.  Bill the appropriate account.
    void handleClick();

    // All other methods omitted for brevity...

  private:
    string adText_;
    string keyword_;
    int bid_;
    Account& account_;
};

====== ad.c ======
  
void Ad::handleClick() {
  switch (account_.getType()) {

    case Account::kCREDIT_CARD_ACCOUNT:
      Biller::submitToBiller(account_.getCreditCardNumber(), bid_);// async call
      break;

    case Account::kPREPAID_ACCOUNT:
      account_.setPrepaidBalance(account_.getPrepaidBalance() - bid_);
      if (account_.getPrepaidBalance() <= 0) {
        account_.setEnabled(false);
        EmailUtil::sendOverdrawnEmail(account_.getEmailAddress()); // async call
      }
      break;

    case Account::kBANK_TRANSFER_ACCOUNT:
      Biller::billBankAccount(account_.getBankRoutingNumber(),
                              account_.getBankAccountNumber(), 
                              bid_); // async call
      break;

    default: 
      // do nothing.        
  }
}

==== account.h ======
  
 // An account hold the contact information and payment information.
class Account {

  public:
    static const int kCREDIT_CARD_ACCOUNT = 0;
    static const int kPREPAID_ACCOUNT = 1;
    static const int kBANK_TRANSFER_ACCOUNT = 2;

    
    

    void setEnabled(bool enabled) { enabled_ = enabled; }

  private:
    string bankAccountNumber_;
    string bankRoutingNumber_;
    string creditCardNumber_;
    string emailAddress_;
    int prepaidBalance_;
    int type_;
    bool enabled_;
};