What is the difference between new and malloc?

Question

Accepted Answer

**new** — C++ operator. **malloc** — C function.

**new:**
```cpp
// Allocate single object
int* ptr = new int(10);  // Initialize with 10

// Allocate array
int* arr = new int[5];  // No initialization
int* arr2 = new int[5]{1, 2, 3, 4, 5};  // C++11

// Calls constructor
MyClass* obj = new MyClass();

// Returns typed pointer
int* p = new int;  // int*

// Deallocate
delete ptr;
delete[] arr;
```

**malloc:**
```cpp
#include <cstdlib>

// Allocate memory
int* ptr = (int*)malloc(sizeof(int));

// Array
int* arr = (int*)malloc(5 * sizeof(int));

// No constructor call!
MyClass* obj = (MyClass*)malloc(sizeof(MyClass));

// Returns void*
void* p = malloc(100);

// Deallocate
free(ptr);
```

**Key differences:**
- **new** — calls constructor, **malloc** — does not.
- **new** — returns typed pointer, **malloc** — void*.
- **new** — C++ operator, **malloc** — C function.
- **new** — use delete, **malloc** — use free.
- **new** — can be overloaded, **malloc** — cannot.

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