c++ - Operator New in function call -

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void f(a* a) {     delete a;  };  f(new a());

will delete operator release allocated memory or must create , delete object this: 

f(a* a) {}   a = new a(); f(a); delete a;

yes free memory, preferred use smart pointers such std::shared_ptr or boost::shared_ptr prior c++11 instead. in example better set freed pointer null avoid double deallocation avoiding dangling pointer errors.

void f(a*& a) {     delete a;      = null; };

you not able call f(new a()); thru , require pass reference pointer holding variable. in 2nd variant. there should a* = new a(); there thru, indicate a pointer.


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