array using new c++ code example

Example 1: declare dynamic array c++

int main()
{
  int size;

  std::cin >> size;

  int *array = new int[size];

  delete [] array;

  return 0;
}

Example 2: how to dynamically allocate an array c++

int* a = NULL;   // Pointer to int, initialize to nothing.
int n;           // Size needed for array
cin >> n;        // Read in the size
a = new int[n];  // Allocate n ints and save ptr in a.
for (int i=0; i<n; i++) {
    a[i] = 0;    // Initialize all elements to zero.
}
. . .  // Use a as a normal array
delete [] a;  // When done, free memory pointed to by a.
a = NULL;     // Clear a to prevent using invalid memory reference.

Example 3: how to make an array c++

int foo [] = { 16, 2, 77, 40, 12071 };

Example 4: arrays in c++

#include <iostream>
#include <array> //for using std::array

int main()
{

	int example[5];//array on stack
	int* another = new int[5];//array on heap
	delete[] another;//freeing up memory on heap
	example[0] = 1;
	example[1] = 2;
	example[2] = 3;
	example[3] = 4;
	for (int i = 0; i < 5; i++) {
		example[i] = 2;
	}
	int* ptr = example;//arrays are just pointers to the begining of the block of memory
	example[2] = 5;
	*(ptr + 2) = 6;//adding 4+4 bytes to ptr
	std::cout << example[2] << std::endl;//output => 6
	*(int*)((char*)ptr + 8) = 8;//adding 8 bytes to ptr using ptr arithmetic
	std::cout << example[2] << std::endl;//output => 8
	//std::array provide some additional functionality like bounce checking size checking but do have a performance overhead
	std::array<int,5> stda;//creating an array named stda of int 5 size
	std::cout << stda.size() << std::endl;//will output size of std::array ,output =>5   
    std::cin.get();
}

Example 5: how to array in c++

int foo [5] = { 16, 2, 77, 40, 12071 };

Example 6: c++ allocate dynamic with initial values

int length = 50;
int *array = new int[length]();
// returns 50 length array of 0