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#include <fstream>
#include <iostream>
#include <string>
using namespace std;
class String
{
union Ptrs
{
void *vp;
String *sp;
size_t *np;
};
std::string d_str;
public:
String(std::string const &txt)
:
d_str(txt)
{}
~String()
{
cout << "destructor: " << d_str << '\n';
}
static String *construct(istream &in, size_t n)
{
Ptrs p = {operator new(n * sizeof(String) + sizeof(size_t))};
*p.np++ = n;
string line;
for (size_t idx = 0; idx != n; ++idx)
{
getline(in, line);
new(p.sp + idx) String{ line };
}
return p.sp;
}
static void destroy(String *sp)
{
Ptrs p = {sp};
--p.np;
for (size_t n = *p.np; n--; )
sp++->~String();
operator delete(p.vp);
}
};
int main()
{
String *sp = String::construct(cin, 5);
String::destroy(sp);
}
/*
After providing 5 lines containing, respectively
alpha, bravo, charley, delta, echo
the program displays:
destructor: alpha
destructor: bravo
destructor: charley
destructor: delta
destructor: echo
*/
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