#include <iostream>
using namespace std;

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

   friend BString operator+(const BString& x, const BString& y);

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

public:
   BString();		// default constructor -- sets to empty string
   BString(const char* c);	// conversion FROM c-string to string object
   BString(int x);		// conversion from int to string object

   ~BString();		// destructor for final cleanup

   // deep copy functions
   BString(const BString& s);			// copy constructor
   BString& operator=(const BString& s);	// assignment operator

   int GetSize() const;		// retrieve the size of the string
   BString Substring(int index, int len);	// return a substring starting
						//   at index with length len

private:
   char* str;		// the pointer to our dynamic array of chars
   int size;		// the size of the string (e.g. "Hello" would be 5)
			//   we will allocate just what we need to store

   void Resize(int newsize);	// resize the string to size "newsize"
};