newstr.cpp

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// newstr.cpp
// using new to get memory for strings
#include <iostream>
#include <cstring>       //for strcpy(), etc
using namespace std;
////////////////////////////////////////////////////////////////
class String             //user-defined string type
   {
   private:
      char* str;                    //pointer to string
   public:
      String(char* s)               //constructor, one arg
         {
         int length = strlen(s);    //length of string argument
         str = new char[length+1];  //get memory
         strcpy(str, s);            //copy argument to it
         }
      ~String()                     //destructor
         {
         cout << "Deleting str\n";
         delete[] str;              //release memory
         }
      void display()                //display the String
         {
         cout << str << endl;
         }
   };
////////////////////////////////////////////////////////////////
int main()
   {                                //uses 1-arg constructor
   String s1 = "Who knows nothing doubts nothing.";

   cout << "s1=";                   //display string
   s1.display();
   return 0;
   }