Usage of new in c++

The new operator in C is used for dynamic memory allocation, allocating a specified size of memory from the heap memory and returning a pointer to the allocated memory. Usage methods include: 1. Allocate memory: use the new operator to allocate the required size of memory; 2. Access the allocated memory: access the allocated memory through the returned pointer; 3. Release the allocated memory: use the delete operator to release no longer Dynamically allocate memory as needed.

Usage of new in C

The new operator is the basic tool in C for dynamic memory allocation. It allocates memory of the specified size from heap memory and returns a pointer to the allocated memory.

Syntax

<code class="cpp">void* new(size_t size);</code>

Where:

• size is the memory size to be allocated (in bytes ).
• The return value is a void* pointer pointing to the allocated memory.

Usage

The steps to allocate memory using new are as follows:

1. Allocate memory: use new operator to allocate The required size of memory. For example:

   <code class="cpp">int* ptr = new int;</code>

2. Access allocated memory: Access allocated memory through the returned pointer. For example:

   <code class="cpp">*ptr = 10;</code>

3. Release allocated memory: Use the delete operator to release dynamically allocated memory that is no longer needed. For example:

   <code class="cpp">delete ptr;</code>

Note

• The new operator may throw a std::bad_alloc exception if it cannot allocate enough Memory.
• You must always use the delete operator to release dynamically allocated memory that is no longer needed to avoid memory leaks.
• The new operator can only be used to allocate raw memory blocks (uninitialized), using new to initialize an object will lead to undefined behavior.
• The new operator always returns a void* pointer, which requires type conversion for use.

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