ReverseLinkedList.cpp

// Iterative C++ program to reverse a linked list
#include <iostream>
using namespace std;

/* Link list node */
struct Node {
	int data;
	struct Node* next;
	Node(int data)
	{
		this->data = data;
		next = NULL;
	}
};

struct LinkedList {
	Node* head;
	LinkedList() { head = NULL; }

	/* Function to reverse the linked list */
	void reverse()
	{
		// Initialize current, previous and next pointers
		Node* current = head;
		Node *prev = NULL, *next = NULL;

		while (current != NULL) {
			// Store next
			next = current->next;
			// Reverse current node's pointer
			current->next = prev;
			// Move pointers one position ahead.
			prev = current;
			current = next;
		}
		head = prev;
	}

	/* Function to print linked list */
	void print()
	{
		struct Node* temp = head;
		while (temp != NULL) {
			cout << temp->data << " ";
			temp = temp->next;
		}
	}

	void push(int data)
	{
		Node* temp = new Node(data);
		temp->next = head;
		head = temp;
	}
};

/* Driver code*/
int main()
{
	/* Start with the empty list */
	LinkedList ll;
	ll.push(20);
	ll.push(4);
	ll.push(15);
	ll.push(85);

	cout << "Given linked list\n";
	ll.print();

	ll.reverse();

	cout << "\nReversed Linked list \n";
	ll.print();
	return 0;
}