Merge pull request #178 from Aniket-Mishra/master

Structure changes and LinkedList added

Author: ionicc

Data_Structure/src/Linked Lists/Doubly_Linked_list.py

@@ -0,0 +1,101 @@
+# -*- coding: utf-8 -*-
+"""
+Created on Thu Oct  3 15:54:30 2019
+
+@author: mishr
+"""
+#doubly Linked List
+
+class Node:
+    
+    def __init__(self, data=None):
+        
+        self.data = data
+        self.next_node = None
+        self.prev_node = None
+        
+class doubly_linked_list:
+    
+    def __init__(self): 
+        self.head = Node()
+        
+    def append(self, data):
+        
+        new_node = Node(data)
+        current = self.head
+        while current.next_node != None:
+            current = current.next_node
+        
+        current.next_node = new_node
+        new_node.prev_node = current
+        new_node.next_node = None
+        
+    def length(self):
+        
+        current = self.head
+        counter = 0
+        while current.next_node != None:
+            counter += 1
+            current = current.next_node
+        
+        return counter
+    
+    def delete_at(self, index):
+        if index >= self.length():
+            print("Index Out Of bounds")
+            return None
+        current_index = 0
+        current_node = self.head
+        while True:
+            last_node = current_node
+            previous_node = current_node.prev_node
+            current_node = current_node.next_node
+            
+            if current_index == index:
+                last_node.next_node = current_node.next_node
+                last_node.prev_node = previous_node
+                return
+            current_index += 1
+     
+    def get_value_at(self, index):
+        
+        if index >= self.length():
+            print("Index Out Of bounds")
+            return None
+        current_index = 0
+        current_node = self.head
+        while True:
+            current_node = current_node.next_node
+            if current_index == index:
+                return current_node.data
+            current_index += 1
+    
+    def display(self):
+        
+        node_list = []
+        current = self.head
+        
+        while current.next_node is not None:
+            
+            current = current.next_node
+            node_list.append(current.data)
+            
+        print(node_list)
+    
+if __name__ == '__main__':
+        
+    dll = doubly_linked_list()
+    
+    dll.append(1)
+    dll.append(2)
+    dll.append(3)
+    dll.append(4)
+    dll.append(5)
+    dll.append(6)
+    dll.append(7)
+    dll.append(8)
+    dll.display()
+    dll.delete_at(3)
+    dll.display()
+    dll.get_value_at(4)
+    

Data_Structure/src/Linked Lists/Singly_Linked_List.py

@@ -0,0 +1,94 @@
+# -*- coding: utf-8 -*-
+"""
+Created on Thu Oct  3 15:13:10 2019
+
+@author: mishr
+"""
+
+#Singly Linked List 
+
+class Node:
+    
+    def __init__(self, data=None, next_node=None):
+        self.data = data
+        self.next_node = next_node
+        
+    
+        
+class singly_linked_list:
+    def __init__(self):
+        
+        self.head = Node()
+    
+    def append(self, data):
+        
+        new_node = Node(data)
+        current = self.head
+        while current.next_node != None:
+            current = current.next_node
+        current.next_node = new_node
+    
+    def length(self):
+        
+        current = self.head
+        counter = 0
+        while current.next_node != None:
+            counter += 1
+            current = current.next_node
+        
+        return counter
+    
+    def get_value_at(self, index):
+        
+        if index >= self.length():
+            print("Index Out Of bounds")
+            return None
+        current_index = 0
+        current_node = self.head
+        while True:
+            current_node = current_node.next_node
+            if current_index == index:
+                return current_node.data
+            current_index += 1
+        
+    def delete_at(self, index):
+        
+        if index >= self.length():
+            print("Index Out Of bounds")
+            return None
+        current_index = 0
+        current_node = self.head
+        while True:
+            last_node = current_node
+            current_node = current_node.next_node
+            if current_index == index:
+                last_node.next_node = current_node.next_node
+                return
+            current_index += 1
+            
+    def display(self):
+        
+        node_list = []
+        current = self.head
+        while current.next_node != None:
+            current = current.next_node
+            node_list.append(current.data)
+            
+        print(node_list)
+    
+if __name__ == '__main__':
+    my_list = singly_linked_list()
+    my_list.append(0)
+    my_list.append(1)
+    my_list.append(2)
+    my_list.append(3)
+    my_list.append(4)
+    my_list.append(5)
+    my_list.display()
+    my_list.get_value_at(3)
+    my_list.delete_at(3)
+    my_list.display()
+    #can use loop to take inputs
+        
+        
+