How to Copy One Array to Another in C++?

In C++, arrays are a type of data structure that stores a fixed-size collection of elements of the same type in a contiguous memory location, and sometimes we need to copy the contents of one array to another. In this article, we will learn how to copy one array to another in C++.

Example:

Input:
arr1 = {10, 20, 30, 40, 50, 60}

Output: 
arr2: {10, 20, 30, 40, 50, 60}

Copy All Elements of One Array to Another Array

For copying all the elements stored in one array to another 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 Use std::copy

copy(strt_iter1, end_iter1, strt_iter2)

Here,

• strt_iter1 is the iterator to the beginning of the first array.
• end_iter1 is the iterator to the end of the first array.
• strt_iter2 is the iterator to the beginning of the second array where we have to copy the elements of the first array.

C++ Program to Copy One Array to Another

The below program demonstrates how we can copy one array to another using copy() function in C++.

C++

// C++ program to illustrate how to copy one array to
// another
#include <algorithm>
#include <iostream>
using namespace std;

// Driver code
int main()
{
    // First array
    int arr1[] = { 10, 20, 30, 40, 50, 60 };
    int n = sizeof(arr1) / sizeof(arr1[0]);

    // Print the first array
    cout << "Array 1: ";
    for (int i = 0; i < n; i++)
        cout << arr1[i] << " ";
    cout << endl;

    // Second array to store the elements of the first array
    int arr2[n];

    // Copy first array to second array
    copy(arr1, arr1 + n, arr2);

    // Print the second array
    cout << "Array 2: ";
    for (int i = 0; i < n; i++)
        cout << arr2[i] << " ";
    cout << endl;

    return 0;
}

Output

Array 1: 10 20 30 40 50 60 
Array 2: 10 20 30 40 50 60 

Time Complexity: O(n), where n is the number of elements being copied.
Auxiliary Space: O(n)