#include <iostream>
using namespace std;

class BString
{
   friend bool operator< (const BString& b1, const BString& b2);
   friend bool operator> (const BString& b1, const BString& b2);
   friend bool operator<= (const BString& b1, const BString& b2);
   friend bool operator>= (const BString& b1, const BString& b2);
   friend bool operator== (const BString& b1, const BString& b2);
   friend bool operator!= (const BString& b1, const BString& b2);

   friend BString operator+(const BString& b1, const BString& b2);

   friend ostream& operator<< (ostream& os, const BString& bs);
   friend istream& operator>> (istream& is, BString& bs);

public:
   BString();			// default, init string to empty
   BString(const char* s);	// conversion constructor
				//  create string from a c-string
   ~BString();
   BString(const BString& bs);			// copy constructor
   BString& operator=(const BString& bs);	// assignment operator
   BString& operator+= (const BString& bs);	// concat and assign

   int Size() const;		// return the size of the string
   BString Substring(int start, int length) const;



private:
   char* str;		// pointer to dynamically allocated string
			//  stored as a char array
   int size;		// tracking variable, size of string
			//  allocated space will always be size + 1

   void Resize(int newsize);	// resize string to newsize

};