How to dynamically allocate arrays in C++

Question

I know how to dynamically allocate space for an array in C. It can be done as follows:

L = (int*)malloc(mid*sizeof(int)); 

and the memory c

Answer 1

Following Info will be useful : Source : https://www.learncpp.com/cpp-tutorial/6-9a-dynamically-allocating-arrays/

Initializing dynamically allocated arrays

If you want to initialize a dynamically allocated array to 0, the syntax is quite simple:

int *array = new int[length]();

Prior to C++11, there was no easy way to initialize a dynamic array to a non-zero value (initializer lists only worked for fixed arrays). This means you had to loop through the array and assign element values explicitly.

int *array = new int[5];
array[0] = 9;
array[1] = 7;
array[2] = 5;
array[3] = 3;
array[4] = 1;

Super annoying!

However, starting with C++11, it’s now possible to initialize dynamic arrays using initializer lists!

int fixedArray[5] = { 9, 7, 5, 3, 1 }; // initialize a fixed array in C++03
int *array = new int[5] { 9, 7, 5, 3, 1 }; // initialize a dynamic array in C++11

Note that this syntax has no operator= between the array length and the initializer list.

For consistency, in C++11, fixed arrays can also be initialized using uniform initialization:

int fixedArray[5] { 9, 7, 5, 3, 1 }; // initialize a fixed array in C++11
char fixedArray[14] { "Hello, world!" }; // initialize a fixed array in C++11

One caveat, in C++11 you can not initialize a dynamically allocated char array from a C-style string:

char *array = new char[14] { "Hello, world!" }; // doesn't work in C++11

If you have a need to do this, dynamically allocate a std::string instead (or allocate your char array and then strcpy the string in).

Also note that dynamic arrays must be declared with an explicit length:

int fixedArray[] {1, 2, 3}; // okay: implicit array size for fixed arrays

int *dynamicArray1 = new int[] {1, 2, 3}; // not okay: implicit size for dynamic arrays

int *dynamicArray2 = new int[3] {1, 2, 3}; // okay: explicit size for dynamic arrays