Compilation error appears because of missing const? - c++

Question

I am trying to run a code that defines objects that are a collection of English letters.
I dont know why it does not compile.
I have tried to change from int to const int but it is not the case,
and also added the disable 4996 message but it didnt help.
#include <iostream>
using namespace std;
class CharSet
{
int size;
char* pSet;
public:
// -----------------------------------
CharSet(int const size, char* set)
{
this->size = size;
pSet = new char[strlen(set) + 1];
strcpy(pSet, set);
}
// -----------------------------------
~CharSet()
{
delete[] pSet;
}
// -----------------------------------
CharSet operator*(const CharSet & other)
{
int maxSize = 0;
if (this->size >= other.size)
maxSize = this->size;
else
maxSize = other.size;
char * ret = new char[maxSize + 1];
char temp;
int index = 0;
for (int i = 0; i < this->size; i++)
{
temp = this->pSet[i];
for (int j = 0; j < other.size; j++)
{
if (other.pSet[j] == temp)
{
ret[index] = temp;
index++;
}
}
}
ret[index] = '\0';
return CharSet(maxSize, ret);
}
// -----------------------------------
bool operator()(char check)
{
bool flag = false;
for (int i = 0; i < this->size; i++)
{
if (pSet[i] == check)
flag = true;
}
return flag;
}
// -----------------------------------
friend ostream& operator<<(ostream& os, const CharSet& s)
{
os << s.pSet;
return os;
}
// -----------------------------------
};
int main()
{
CharSet s1(4, "DAQP"), s2(3, "AXZ");
cout << s1 * s2 << endl;
if (s1('Q') == true)
cout << "The element is member of the set" << endl;
else
cout << "The element is not member of the set" << endl;
return 0;
}
errors:
E0289 no instance of constructor "CharSet::CharSet" matches the argument
E0289 no instance of constructor "CharSet::CharSet" matches the argument list
C4996 'strcpy': This function or variable may be unsafe. Consider using strcpy_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS. See online help for details.
C2664 'CharSet::CharSet(const CharSet &)': cannot convert argument 2 from
C2664 'CharSet::CharSet(const CharSet &)': cannot convert argument 2 from 'const char [4]' to 'char *'

Answer 1

you need a const char* in your constructor:
CharSet(int const size, const char* set)
Thanks to
#holy black cat
"DAQP" is a const char[] which you didn't provide a constructor for that(the array will implicitly convert to pointer).
A better way is using std::string:
class CharSet
{
std::string pSet;
public:
// -----------------------------------
CharSet(std::string set) : pSet(set)
{
}
// -----------------------------------
~CharSet()
{
}
// -----------------------------------
CharSet operator*(const CharSet & other)
{
int maxSize = 0;
std::string ret;
char temp;
int index = 0;
for (int i = 0; i < pSet.size(); i++)
{
temp = pSet[i];
for (int j = 0; j < other.pSet.size(); j++)
{
if (other.pSet[j] == temp)
{
ret += temp;
index++;
}
}
}
return CharSet(ret);
}
// the rest of members ...
//
};
full code at godblot