strequal.cpp

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//strequal.cpp
//overloaded '==' operator compares strings
#include <iostream>
using namespace std;
#include <string.h>      //for strcmp()
////////////////////////////////////////////////////////////////
class String             //user-defined string type
   {
   private:
      enum { SZ = 80 };                //size of String objects
      char str[SZ];                    //holds a string
   public:
      String()                         //constructor, no args
         { strcpy(str, ""); }
      String( char s[] )               //constructor, one arg
         { strcpy(str, s); }
      void display() const             //display a String
         { cout << str; }
      void getstr()                    //read a string
         { cin.get(str, SZ); }
      bool operator == (String ss) const  //check for equality
         {
         return ( strcmp(str, ss.str)==0 ) ? true : false;
         }
   };
////////////////////////////////////////////////////////////////
int main()
   {
   String s1 = "yes";
   String s2 = "no";
   String s3;

   cout << "\nEnter 'yes' or 'no': ";
   s3.getstr();                        //get String from user

   if(s3==s1)                          //compare with "yes"
      cout << "You typed yes\n";
   else if(s3==s2)                     //compare with "no"
      cout << "You typed no\n";
   else
      cout << "You didn't follow instructions\n";
   return 0;
   }