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  1. #include <iostream>
  2. #include <iomanip>
  3.  
  4. using namespace std;
  5.  
  6. class A {
  7. 	public:
  8. 	   int v;
  9. 	   A() {
  10. 	     std::cout << "запуск конструктора ... " << std::endl;
  11. 	     v = 10; //0xA
  12. 	   }
  13. };
  14.  
  15. int main() {
  16. 	// без вызова конструктора -------------------------------
  17. 	char *a = (char*)malloc(1024);
  18. 	A *x = (A*)a;
  19. 	*a++ = 255; // 0xFF
  20. 	*a   = 128; // 0x80
  21. 	std::cout << "x->v: " << std::setbase(16) << x->v << std::endl; 
  22. 	free(--a);
  23. 	// с вызовом конструктора --------------------------------
  24. 	A *y = new A();
  25. 	std::cout << "y->v: " << y->v << std::endl;
  26. 	delete x;
  27. 	// -------------------------------------------------------
  28. 	return 0;
  29. }
Success #stdin #stdout 0s 3228KB
comments (?)
stdin
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Standard input is empty
stdout
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x->v: 80ff
запуск конструктора ... 
y->v: a
https://ideone.com/bpMQps
language:
C++14 (gcc 8.3)
created:
9 years ago
visibility:
public

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