adding-reversing-linkedlist (#62)

* adding-reversing-linkedlist

* changes done

* reverse linkedlist code and index updated

* changes added

* print added

Co-authored-by: cyberghost002 <49005095+cyberghost002@users.noreply.github.com>

linked-lists/README.md

@@ -3,6 +3,7 @@
 ### C or C++
 
 1. [Singly Linked List](c-or-cpp/singly.cpp)
+2. [Reversing Linked List](c-or-cpp/reverse-linkedlist.cpp)
 
 ### Java
 

linked-lists/c-or-cpp/reverse-linkedlist.cpp

@@ -0,0 +1,75 @@
+#include <bits/stdc++.h>
+using namespace std;
+
+struct Node
+{
+    int data;
+    Node *next;
+};
+
+Node *newNode(int data)
+{
+    Node *new_node = new Node;
+    new_node->data = data;
+    new_node->next = NULL;
+    return new_node;
+}
+
+void push(Node **head_ref, int new_data)
+{
+    Node *new_node = new Node();
+    new_node->data = new_data;
+    new_node->next = (*head_ref);
+    (*head_ref) = new_node;
+}
+
+Node *reverseList(Node *A)
+{
+    Node *current, *prev, *next;
+    current = A;
+    prev = NULL;
+    next = NULL;
+    while (current != NULL)
+    {
+
+        // storing address of node next to current
+        next = current->next;
+
+        // reversing the link of current node
+        current->next = prev;
+
+        // updating prev and current
+        prev = current;
+        current = next;
+    }
+
+    current = prev;
+
+    return current;
+}
+
+void printlist(Node *head)
+{
+    while (head != NULL)
+    {
+        cout << head->data << " ";
+        head = head->next;
+    }
+    cout << endl;
+}
+
+int32_t main()
+{
+    Node *head = NULL;
+    push(&head, 5);
+    push(&head, 7);
+    push(&head, 10);
+
+    cout << "Linked list before reversing ->" << endl;
+    printlist(head);
+
+    head = reverseList(head);
+
+    cout << "Linked list after reversing ->" << endl;
+    printlist(head);
+}