How to Copy a Vector to an Array in C++?

In C++, vectors are dynamic arrays that can grow and reduce in size as per requirements. Sometimes, we may need to copy the contents of a vector to the POD array. In this article, we will learn how to copy a vector to an array in C++.

Example:

Input: 
myVec = {10,20,30,40,50,60};

Output: 
array: {10,20,30,40,50,60}

Convert Vector to an Array in C++

For copying the elements stored in a std::vector to an array in C++, we can use the std::copy() function provided in the STL <algorithm> library that copies a range of elements from one container to another.

Syntax to of std::copy()

copy (first, last, result);

Here,

• first is the iterator to the beginning of the vector.
• last is the iterator to the end of the vector.
• result is the iterator to the beginning of the array.

C++ Program to Copy a Vector to an Array

The below program demonstrates how we can copy a vector to an array using copy() in C++.

C++

// C++ program to illustrate how to copy a vector to an
// array
#include <algorithm>
#include <iostream>
#include <vector>
using namespace std;

// Driver code
int main()
{
    // Vector
    vector<int> vec = { 10, 20, 30, 40, 50, 60 };

    // Print the vector
    cout << "Vector: ";
    for (int i = 0; i < vec.size(); i++)
        cout << vec[i] << " ";
    cout << endl;

    // Array to store the vector elements
    int arr[vec.size()];

    // Copy vector to array
    copy(vec.begin(), vec.end(), arr);

    // Print the array
    cout << "Array: ";
    for (int i = 0; i < vec.size(); i++)
        cout << arr[i] << " ";
    cout << endl;

    return 0;
}

Output

Vector: 10 20 30 40 50 60 
Array: 10 20 30 40 50 60 

Time Complexity: O(N), here N is the size of the vector.
Auxiliary Space: O(1)