Singly Linked List implementation in Python

Author: OmkarPathak

Linked Lists/SinglyLinkedList.py

@@ -0,0 +1,113 @@
+# Author: OMKAR PATHAK
+
+# Linked List and Node can be accomodated in separate classes for convenience
+
+class Node(object):
+    # Each node has its data and a pointer that points to next node in the Linked List
+    def __init__(self, data, next = None):
+        self.data = data;
+        self.next = next;
+
+    # function to set data
+    def setData(self, data):
+        self.data = data;
+
+    # function to get data of a particular node
+    def getData(self):
+        return self.data
+
+    # function to set next node
+    def setNext(self, next):
+        self.next = next
+
+    # function to get the next node
+    def getNext(self):
+        return self.next
+
+class LinkedList(object):
+    # Defining the head of the linked list
+    def __init__(self):
+        self.head = None
+
+    # printing the data in the linked list
+    def printLinkedList(self):
+        temp = self.head
+        while(temp):
+            print(temp.data, end=' ')
+            temp = temp.next
+
+    # inserting the node at the beginning
+    def insertAtStart(self, data):
+        if self.head == None:
+            newNode = Node(data)
+            self.head = newNode
+        else:
+            newNode = Node(data)
+            newNode.next = self.head
+            self.head = newNode
+
+    # inserting the node in between the linked list (after a specific node)
+    def insertBetween(self, previousNode, data):
+        if (previousNode.next is None):
+            print('Previous node should have next node!')
+        else:
+            newNode = Node(data)
+            newNode.next = previousNode.next
+            previousNode.next = newNode
+
+    # inserting at the end of linked list
+    def insertAtEnd(self, data):
+        newNode = Node(data)
+        temp = self.head
+        while(temp.next != None):         # get last node
+            temp = temp.next
+        temp.next = newNode
+
+    # deleting an item based on data(or key)
+    def delete(self, data):
+        temp = self.head
+        # if data/key is found in head node itself
+        if (temp.next is not None):
+            if(temp.data == data):
+                self.head = temp.next
+                temp = None
+                return
+            else:
+                #  else search all the nodes
+                while(temp.next != None):
+                    if(temp.data == data):
+                        break
+                    prev = temp          #save current node as previous so that we can go on to next node
+                    temp = temp.next
+
+                # node not found
+                if temp == None:
+                    return
+
+                prev.next = temp.next
+                return
+
+    # iterative search
+    def search(self, node, data):
+        if node == None:
+            return False
+        if node.data == data:
+            return True
+        return self.search(node.getNext(), data)
+
+if __name__ == '__main__':
+    List = LinkedList()
+    List.head = Node(1)                # create the head node
+    node2 = Node(2)
+    List.head.setNext(node2)           # head node's next --> node2
+    node3 = Node(3)
+    node2.setNext(node3)               # node2's next --> node3
+    List.insertAtStart(4)              # node4's next --> head-node --> node2 --> node3
+    List.insertBetween(node2, 5)       # node2's next --> node5
+    List.insertAtEnd(6)
+    List.printLinkedList()
+    print()
+    List.delete(3)
+    List.printLinkedList()
+    print()
+    print(List.search(List.head, 1))