Reverse Link List Iterrative

ReverseLinkList.py

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+from sys import stdin, setrecursionlimit
+setrecursionlimit(10 ** 6)
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+#Following is the Node class already written for the Linked List
+class Node :
+    def __init__(self, data) :
+        self.data = data
+        self.next = None
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+
+#Iterative Approach
+def Reverse(head):
+    curr = head
+    prev = None
+    while (curr is not None):
+        next = curr.next
+        curr.next = prev
+        prev = curr
+        curr = next
+    return prev     #As our head is now prev
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+#Taking Input Using Fast I/O
+def takeInput() :
+    head = None
+    tail = None
+
+    datas = list(map(int, stdin.readline().rstrip().split(" ")))
+
+    i = 0
+    while (i < len(datas)) and (datas[i] != -1) :
+        data = datas[i]
+        newNode = Node(data)
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+        if head is None:
+            head = newNode
+            tail = newNode
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+        else :
+            tail.next = newNode
+            tail = newNode
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+        i += 1
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+    return head
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+
+#to print the linked list 
+def printLinkedList(head) :
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+    while head is not None :
+        print(head.data, end = " ")
+        head = head.next
+
+    print()
+
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+#main
+t = int(stdin.readline().rstrip())
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+while t > 0 :
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+    head = takeInput()
+    head = Reverse(head)
+    printLinkedList(head)
+    print()
+
+    t -= 1