Delete last node of linked list in c++

C++ program for Delete last node of linked list. Here problem description and explanation.

// Include header file
#include <iostream>
using namespace std;
/*
    C++ program for
    Delete the last node of singly linked list
*/
// Linked list node
class LinkNode
{
	public: 
    int data;
	LinkNode *next;
	LinkNode(int data)
	{
		this->data = data;
		this->next = nullptr;
	}
};
class SingleLL
{
	public: LinkNode *head;
	LinkNode *tail;
	SingleLL()
	{
		this->head = nullptr;
		this->tail = nullptr;
	}
	// Add new node at the end of linked list
	void addNode(int value)
	{
		// Create a new node
		LinkNode *node = new LinkNode(value);
		if (this->head == nullptr)
		{
			this->head = node;
		}
		else
		{
			this->tail->next = node;
		}
		// Set new last node
		this->tail = node;
	}
	// Display linked list element
	void display()
	{
		if (this->head == nullptr)
		{
			cout << "Empty Linked List" << endl;
			return;
		}
		LinkNode *temp = this->head;
		// iterating linked list elements
		while (temp != nullptr)
		{
			cout << temp->data << " → ";
			// Visit to next node
			temp = temp->next;
		}
		cout << "NULL" << endl;
	}
	// Delete last node of singly linked list
	void deleteLastNode()
	{
		if (this->head == nullptr)
		{
			cout << "Empty Linked List" << endl;
			return;
		}
		else
		{
			LinkNode *temp = this->head;
			LinkNode *find = nullptr;
			// Find second last node
			while (temp->next != nullptr)
			{
				find = temp;
				temp = temp->next;
			}
			if (find == nullptr)
			{
				// Delete head node of linked list
				this->head = nullptr;
				this->tail = nullptr;
			}
			else
			{
				// Set new last node
				this->tail = find;
				find->next = nullptr;
			}
		}
	}
};
int main()
{
	SingleLL *sll = new SingleLL();
	// Linked list
	// 1 → 2 → 3 → 4 → 5 → 6 → NULL
	sll->addNode(1);
	sll->addNode(2);
	sll->addNode(3);
	sll->addNode(4);
	sll->addNode(5);
	sll->addNode(6);
	cout << "Before Delete " << endl;
	sll->display();
	sll->deleteLastNode();
	cout << "After Delete " << endl;
	sll->display();
	return 0;
}

Output

Before Delete
1 → 2 → 3 → 4 → 5 → 6 → NULL
After Delete
1 → 2 → 3 → 4 → 5 → NULL


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