How to define dynamic array in c++

In C, dynamic arrays can allocate and free memory at runtime. The steps to define a dynamic array include: (1) allocate memory using the new operator; (2) initialize the array elements; (3) use the dynamic array; (4) use the delete[] operator to release the memory.

How to define a dynamic array in C

In C, a dynamic array is a type that can be used## The #new and delete operators allocate and free memory for array types at runtime. The following are the steps to define a dynamic array:

1. Allocate memory using the new operator

new operator Used to dynamically allocate memory of a specified type and size. For an integer dynamic array, the syntax is as follows:

<code class="cpp">int *array = new int[size];</code>

• array is a pointer variable pointing to the dynamic array.
• size is the size of the array.

2. Initialize array elements

[]) to initialize elements as follows:

<code class="cpp">for (int i = 0; i < size; i++) {
  array[i] = i;
}</code>

3. Using dynamic arrays

sizeof operator to get the size of the array, as shown below:

<code class="cpp">int array_size = sizeof(array) / sizeof(array[0]);</code>

4. Release memory

delete[] operator to free the allocated memory. This will free the memory pointed to by the array elements and pointer variables. The syntax is as follows:

<code class="cpp">delete[] array;</code>

Example

<code class="cpp">#include <iostream>

using namespace std;

int main() {
  int size = 5;
  int *array = new int[size];

  // 初始化数组元素
  for (int i = 0; i < size; i++) {
    array[i] = i * i;
  }

  // 打印数组元素
  for (int i = 0; i < size; i++) {
    cout << array[i] << " ";
  }

  cout << endl;

  // 释放内存
  delete[] array;

  return 0;
}</code>

<code>0 1 4 9 16</code>

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