reverse linked list.py

Author: raianmol172

reverse linked list.py

@@ -0,0 +1,43 @@
+class Node:
+    def __init__(self, data):
+        self.data = data
+        self.next = None
+
+
+class LinkedList:
+    def __init__(self):
+        self.head = None
+
+    def printList(self):
+        temp = self.head
+        while temp:
+            print(temp.data)
+            temp = temp.next
+
+# 10 -> 20 -> 30 -> 40
+# 40 -> 30 -> 20 -> 10
+# 10 <- 20 <- 30 <- 40
+    def reverse_iterative(self):
+        prev = None
+        curr = self.head
+        while curr:
+            nxt = curr.next
+            curr.next = prev
+            prev = curr
+            curr = nxt
+        self.head = prev
+
+
+l1 = LinkedList()
+l1.head = Node(10)
+l2 = Node(20)
+l3 = Node(30)
+l4 = Node(40)
+l1.head.next = l2
+l2.next = l3
+l3.next = l4
+print("before reversing the nodes")
+l1.printList()
+l1.reverse_iterative()
+print("after reversing the nodes")
+l1.printList()