cpp 12.1

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strngbad.h

#pragma once#include<iostream>class StringBad{private:char*str;int len;static int num_strings;public:StringBad(const char*s);StringBad();~StringBad();friend std::ostream & operator<<(std::ostream & os,const StringBad & st);};

strngbad.cpp

#include<cstring>#include"strngbad.h"using std::cout;int StringBad::num_strings = 0;StringBad::StringBad(const char*s){len = std::strlen(s);str = new char[len + 1];std::strcpy(str, s);num_strings++;cout << num_strings << ":\"" << str<< "\"object created\n";}StringBad::StringBad(){len = 4;str = new char[4];std::strcpy(str, "c++");num_strings++;cout << num_strings << ":\"" << str<< "\"default object created\n";}StringBad::~StringBad(){cout << "\"" << str << "\"object deleted, ";--num_strings;cout << num_strings << " left\n";delete[] str;}std::ostream & operator<<(std::ostream & os, const StringBad & st){os << st.str;return os;}

vegnews.cpp

#include<iostream>using std::cout;#include"strngbad.h"void callmel(StringBad &);void callme2(StringBad);int main(){using std::endl;{cout << "Starting an inner block.\n";StringBad headline1("Celery Stalks at Midnight");StringBad headline2("Lettuce Prey");StringBad sports("Spinash Leaves Bowl for Dollars");cout << "headline1: " << headline1 << endl;cout << "headline2: " << headline2 << endl;cout << "sports: " << sports << endl;callme1(headline1);cout << "headline1: " << headline1 << endl;callme2(headline2);cout << "headline2: " << headline2 << endl;cout << "Initalize one object to another:\n";StringBad sailor = sports;cout << "sailor: " << sailor << endl;cout << "Asssign one object to another:\n";StringBad knot;knot = headline1;cout << "knot: " << knot << endl;cout << "Exiting the block.\n";}cout << "End of main()\n";system("pause");return 0;}void callme1(StringBad & rsb){cout << "StringBad passed by reference:\n";cout << "  \"" << rsb << "\"\n";}void callme2(StringBad sb){cout << "String passed by value:\n";cout << "  \""<<sb<<"\"\n";}

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