C++ .back()

The C++ .back() method is used to access the element at the back of the queue without removing it.

C++ .back() Syntax

queueName.back();

Parameters:

The C++ .back() method takes no parameters.

Return value:

Returns a reference to the element at the end of the queue.

Example 1: Basic usage of C++ .back()

This example uses C++ .back() to access the last element of the queue:

#include <iostream>
#include <queue>
using namespace std;

int main() {
  // Declaring a queue
  queue<int> q;

  // Inserting int elements into the queue
  q.push(10);
  q.push(20);
  q.push(30);

  // Print the last element of the queue
  cout <<"Last element: " << q.back() << endl;
}

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Here is the output of this code:

Last element: 30

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Example 2: Using C++ .back() with .push()

This example uses C++ .back() to return the last element of the queue after we used .push():

#include <iostream>
#include <queue>
using namespace std;

int main () {
  queue<string> q;

  q.push("Jhon");
  q.push("Bob");
  q.push("Doe");

  cout <<"Last element: " << q.back() << endl;
  q.push("Alice");
  cout <<"Last element after push: " << q.back() << endl;
}

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Here is the output of this code:

Last element: Doe
Last element after push: Alice

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Codebyte Example: Modifying the Last Element Using C++ .back()

This codebyte example uses C++ .back() to modify the last element of the queue:

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