Appending a string w/ a custom operator new

gistfile1.txt

#include <new>
#include <string>
#include <iostream>

char heap[1000];
char *next = heap;

void * operator new (std::size_t sz) { char *ret = next; next += sz; return ret; }
void   operator delete (void *) noexcept {}

int main ()
{
	std::cout << "heap = " << (void *) heap << " next = " << (void *) next << std::endl;
	std::string str;
	str.append("0123456789012345678901234567890123456789");
	std::cout << "p = " << (void *) str.data() << std::endl;
	std::cout << "heap = " << (void *) heap << " next = " << (void *) next << std::endl;
	std::cout << "heap = " << (void *) heap << " next = " << (void *) next << std::endl;	
}