Remove All Elements from a Deque in C++
To clear all elements from a std::deque in C++, we can use the std::deque::clear() function that is used to remove all the elements from the deque container, thus making the deque empty.
Syntax
deque_Name.clear();
C++ Program to Clear All Elements from a Deque
The below program demonstrates how we can use clear() function to remove all elements from a deque in C++.
// C++ program to demonstrate how we can use clear()
// function to remove all elements from a deque
#include <deque>
#include <iostream>
using namespace std;
int main()
{
// Creating a deque
deque<int> dq = { 10, 20, 30, 40 };
// Printing the elements of the deque
cout << "Deque Elements:";
for (int ele : dq) {
cout << ele << " ";
}
cout << endl;
// Printing the size of the deque before clearing it
cout << "Before clearing, the deque has " << dq.size()
<< " elements" << endl;
// Clearing the deque
dq.clear();
// Printing the size of the deque after clearing it
cout << "After clearing, the deque has " << dq.size()
<< " elements" << endl;
return 0;
}
Output
Deque Elements:10 20 30 40 Before clearing, the deque has 4 elements After clearing, the deque has 0 elements
Time Complexity: O(1), where N is the size of the deque.
Auxiliary Space: O(1)
How to Clear All Elements from a Deque in C++?
In C++, deque also known as double-ended queue is a container provided by the Standard Template Library (STL) that allows efficient insertion and deletion at both ends. In this article, we will learn how to clear all elements from a deque in C++.
Example:
Input: myDeque = {10, 20, 30, 40}; Output: After clearing, the deque is empty
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