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// string1.h -- fixed and augmented string class definition
#ifndef STRING1_H_
#define STRING1_H_
#include <iostream>
using std::ostream;
using std::istream;
class String
{
private:
    char * str; // pointer to string
    int len; // length of string
    static int num_strings; // number of objects
    static const int CINLIM = 80; // cin input limit
public:
    // constructors and other methods
    String(const char * s); // constructor
    String(); // default constructor
    String(const String &); // copy constructor
    ~String(); // destructor
    int length () const { return len; }
    // overloaded operator methods
    String & operator=(const String &);
    String & operator=(const char *);
    char & operator[](int i);
    const char & operator[](int i) const;
    // overloaded operator friends
    friend bool operator<(const String &st, const String &st2);
    friend bool operator>(const String &st1, const String &st2);
    friend bool operator==(const String &st, const String &st2);
    friend ostream & operator<<(ostream & os, const String & st);
    friend istream & operator>>(istream & is, String & st);
    // static function
    static int HowMany();
};
#endif

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// string1.cpp -- String class methods
#include <cstring> // string.h for some
#include "string1.h" // includes <iostream>
using std::cin;
using std::cout;
// initializing static class member
int String::num_strings = 0;
// static method
int String::HowMany()
{
    return num_strings;
}
// class methods
String::String(const char * s) // construct String from C string
{
    len = std::strlen(s); // set size
    str = new char[len + 1]; // allot storage
    std::strcpy(str, s); // initialize pointer
    num_strings++; // set object count
}
String::String() // default constructor
{
    len = 4;
    str = new char[1]; // to match delete [] str
    str[0] = '\0'; // default string
    num_strings++;
}
String::String(const String & st)
{
    num_strings++; // handle static member update
    len = st.len; // same length
    str = new char [len + 1]; // allot space
    std::strcpy(str, st.str); // copy string to new location
}
String::~String() // necessary destructor
{
    --num_strings; // required
    delete [] str; // required
}
// overloaded operator methods
// assign a String to a String
String & String::operator=(const String & st)
{
    if (this == &st)
        return  *this;
    delete [] str;
    len = st.len;
    str = new char[len + 1];
    std::strcpy(str, st.str);
    return *this;
}
// assign a C string to a String
String & String::operator=(const char * s)
{
    delete [] str;
    len = std::strlen(s);
    str = new char[len + 1];
    std::strcpy(str, s);
    return *this;
}
// read-write char access for non-const String
char & String::operator[](int i)
{
    return str[i];
}
// read-only char access for const String
const char & String::operator[](int i) const
{
    return str[i];
}
// overloaded operator friends
bool operator<(const String &st1, const String &st2)
{
    return (std::strcmp(st1.str, st2.str) < 0);
}
bool operator>(const String &st1, const String &st2)
{
    return st2 < st1;
}
bool operator==(const String &st1, const String &st2)
{
    return (std::strcmp(st1.str, st2.str) == 0);
}
// simple String output
ostream & operator<<(ostream & os, const String & st)
{
    os << st.str;
    return os;
}
// quick and dirty String input
istream & operator>>(istream & is, String & st)
{
    char temp[String::CINLIM];
    is.get(temp, String::CINLIM);
    if (is)
        st = temp;
    while (is && is.get() != '\n')
        continue;
    return is;
}