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//Class declaration in header.h
#ifndef HEADER_H
#defined HEADER_H
class Strings
{
private:
char * str;
int len;
static int numb_count;
public:
//class methos
Strings();
Strings(const char * s);
Strings (const Strings & s);
//overloaded methods
Strings &operator=(const Strings & s);
Strings & operator=(const char * s);
~Strings() {delete [] str;}
friend bool operator>(const Strings & s, const Strings &c);
friend bool operator<(const Strings & s, const Strings &c);
friend bool operator==(const Strings & s, const Strings & c);
friend std::ostream &operator<<(std::ostream & os, Strings & s);
friend std::istream & operator>>(std::istream & is, Strings & s);
friend Strings operator+(const Strings & s, const Strings & b);
void stringup();
void stringlow();
int charnum(char s);
const char operator[] (int i);
const char operator[] (int i) const;
static int How_to();
int length() const {return len;}
endif // HEADER_H
// the class implementation in another file
int Strings::numb_count = 0;
int Strings::How_to()
{
return numb_count;
}
Strings::Strings(const char * s) // copy a const string to an object
{
len = strlen(s);
str = new char[len + 1];
strcpy(str, s);
numb_count++;
}
Strings::Strings() // default constructor
{
len = 0;
str = new char[1];
str[0] = '\0';
numb_count++;
}
Strings::Strings(const Strings & s) // explicit copy constructor
{
len = s.len;
str = new char[len + 1];
strcpy(str, s.str);
numb_count++;
}
Strings &Strings::operator=(const Strings & s) //assign or initialize an object to another
{
if (this == &s)
return *this;
delete [] str;
len = s.len;
str = new char[len + 1];
strcpy(str, s.str);
return *this;
}
Strings &Strings::operator=(const char * s) // assign or initialize const string to a class object
{
delete [] str;
len = strlen(s);
str = new char[len + 1];
strcpy(str, s);
return *this;
}
bool operator>(const Strings & c, const Strings & b)
//compare string objects
{
return (strcmp(c.str, b.str) > 0);
}
bool operator<(const Strings & c, const Strings & b)//compare string objects
{
return (strcmp(c.str, b.str) < 0);
}
bool operator==(const Strings & c, const Strings & b) // compare string objects
{
return (strcmp(c.str, b.str) == 0);
}
const char Strings::operator[](int i)
{
return str[i];
}
const char Strings::operator[](int i) const // return a char element of an abject
{
return str[i];
}
std::ostream &operator<<(std::ostream &os, Strings & c) // display a string object
{
cout << c.str << endl;
return os;
}
std::istream & operator>>(std::istream & is, Strings & c) // store a string to in an object
{
char temp[80];
is.get(temp, 80);
if (is)
c = temp;
while (is && is.get() != '\n')
continue;
return is;
}
void Strings::stringup() // convert string to uppercase character
{
int i;
for (i = 0; str[i] != '\0'; i++)
{
str[i] = toupper(str[i]);
}
}
void Strings::stringlow() // convert strings to lowercase characters
{
for (int i = 0; str[i] != '\0'; i++)
str[i] = tolower(str[i]);
}
int Strings::charnum(char s) // count how many time a char character appeared in a strings object.
{
int numb = 0;
for (int i = 0; str[i] != '\0'; i++)
{
if (str[i] == s)
numb++;
}
return numb;
}
// this is the overloaded function that seems to go wrong somewhere
Strings operator+(const Strings & s, const Strings & b)
{
Strings temp;
temp = strcat(s.str, b.str);
temp.str = strcat(s.str, b.str);
return temp;
I used each of the above codes by commenting out the other, but the problem still persist.
}
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