#include <cstring>    //for the function strlen
#include <algorithm>  //for the function copy_n
#include <stdexcept>  //for class out_of_range
#include "mystring.h"
using namespace std;

mystring::mystring(const char *initial_p)    //plain old constructor
	: n {strlen(initial_p) + 1}, p {new char[n]}
{
	copy_n(initial_p, n, p);
}

mystring::mystring(const mystring& another)  //"copy" constructor
	: n {another.n}, p {new char[n]} 
{
	copy_n(another.p, n, p);
}

mystring& mystring::operator=(const mystring& another)
{
	if (this != &another) {
		delete[] p;
		p = new char[another.n];
		copy_n(another.p, n, p);
	}
	return *this;
}

char mystring::operator[](size_t i) const
{
	if (i >= n) {
		throw out_of_range("mystring subscript too big");
	}
	return p[i];
}

char& mystring::operator[](size_t i)
{
	if (i >= n) {
		throw out_of_range("mystring subscript too big");
	}
	return p[i];
}