What is the difference between new and malloc in C++?

Point	new / delete	malloc / free
Language	C++	C (also usable in C++)
Constructor	Called	Not called
Return type	The correct pointer type	void* (needs a cast)
On failure	Throws std::bad_alloc	Returns NULL
Size	Calculated by the compiler	You give the bytes

#include <iostream>

struct Item {
    Item() { std::cout << "constructed\n"; }
    ~Item() { std::cout << "destroyed\n"; }
};

int main() {
    Item* p = new Item;       // allocates and constructs
    delete p;                 // destroys and frees
}

In modern C++ do not write them by hand. Use std::make_unique and containers. See Dynamic Memory and Smart Pointers.

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