what is dynamic memory allocation in c code example

Example 1: dynamic memory allocation

int *p = new int; // request memory
*p = 5; // store value

cout << *p << endl; // Output is 5

delete p; // free up the memory

cout << *p << endl; // Output is 0

Example 2: allocate memory c

// Use malloc to allocate memory
ptr = (castType*) malloc(size);
int *exampl = (int*) malloc(sizeof(int));
// Use calloc to allocate and inizialize n contiguous blocks of memory
ptr = (castType*) calloc(n, size);
char *exampl = (char*) calloc(20, sizeof(char));

Example 3: how to use malloc in c

int* a =(int*)malloc(sizeof(int))

Example 4: what is dynamic memory allocation in c++

In the dynamic memory allocation the memory is allocated during run time.
The space which is allocated dynamically usually placed in a program segment which is known as heap.
In this, the compiler does not need to know the size in advance.
In C++, dynamic memory allocation means performing memory allocation manually by programmer.
It is allocated on the heap and the heap is the region of a computer memory which is managed by the programmer using pointers to access the memory.
The programmers can dynamically allocate storage space while the program is running but they cannot create a new variable name.
  
Example:

Example 5: how to use malloc in c

ptr = (castType*) malloc(size);

Example 6: dynamic memory allocation in c++

char* pvalue  = NULL;         // Pointer initialized with null
pvalue  = new char[20];       // Request memory for the variable