Question

in python

11.1 Binary Search Tree In this assignment, you will implement a Binary Search Tree You will also need to implement a Node class. This class will not be tested, but is needed to implement the BST. Your BST must implement the following methods. You are free to implement additional helper methods. It is recommended you create your own helper methods Constructor: Creates an Empty Tree String Method: Returns the string "Empty Tree" for an empty tree. Otherwise, returns a string with the tree in Preorder, Inorder, and Postorder. When printing a Empty/Null node print out the letter N. Put a single space after each value. This means your lines will end with a single extra space. Insert: Insert value x into the tree. Insert ignores duplicated values. Do not insert doubles. find: Returns true/false if value x is in the tree A testbed is provided that will test features of your code. Remember, you can add your own helper methods. Test Bed for Binary Search Tree Class Enter Test Number (1-6): Make a Balanced Tree. Inserting: [6, 8, 4, 3, 7, 5, 9] Your Tree looks like: Preorder: 6 4 3 NN 5 NN 8 7 NN9NN Inorder: N 3N 4N5N 6 N 7 N 8 N9N Postorder: NN 3 NN 5 4 NN 7 NN 9 8 6

Answer 1

Program Code to Copy

class Node:

   

    def __init__(self):

        self.left = None

        self.right = None

        self.data = None

    def __init__(self, data):

        self.left = None

        self.right = None

        self.data = data

# Insert Node

    def insert(self, data):

        if self.data:

            if data < self.data:

                if self.left is None:

                    self.left = Node(data)

                else:

                    self.left.insert(data)

            elif data > self.data:

                if self.right is None:

                    self.right = Node(data)

                else:

                    self.right.insert(data)

        else:

            self.data = data

    def stringMethod(self, root) :

        res = ""

        if root.data is None:

            res = "Empty Tree"

            return res

        else :

            res1 = "\nPreorder: " + str(self.preorderTraversal(root)) + "\n"

            res2 = "Inorder: " + str(self.inorderTraversal(root)) + "\n"

            res3 = "Postorder: " + str(self.postorderTraversal(root)) + "\n"

            res = res1 + res2 + res3

            return res

    def find(self, node, x):

        if (node == None):

            return False

        if (node.data == x):

            return True

        """ then recur on left subtree """

        res1 = self.find(node.left, x)

        """ now recur on right subtree """

        res2 = self.find(node.right, x)

        return res1 or res2

#***************Helper Methods****************************

    # Print the Tree

    def PrintTree(self):

        if self.left:

            self.left.PrintTree()

        print( self.data),

        if self.right:

            self.right.PrintTree()

    # Preorder traversal

    # Root -> Left -> Right

    def preorderTraversal(self, root):

            res = ""

            if root is not None:

                res = res + str(root.data) + " "

                res = res + self.preorderTraversal(root.left)

                res = res + self.preorderTraversal(root.right)

            else:

                res = res + 'N' + " "

            return res

   # Inorder traversal

   # Left -> Root -> Right

    def inorderTraversal(self, root):

        res = ""

        if root:

            res = res + self.inorderTraversal(root.left)

            res = res + str(root.data) + " "

            res = res + self.inorderTraversal(root.right)

        else :

            res = res + 'N' + " "

        return res

    # Postorder traversal

    # Root -> Left -> Right

    def postorderTraversal(self, root):

        res = ""

        if root:

            res = res + self.postorderTraversal(root.left)

            res = res + self.postorderTraversal(root.right)

            res = res + str(root.data) + " "

        else:

            res = res + 'N' + " "

        return res

print("Test Bed for Binary Search Tree Class")

test = input("Enter test Number (1-6):\n")

root = Node(None)

data = [6, 8, 4, 3, 7, 5, 9]

print("Make a Balanced Tree.")

print("Inserting: ", end = " ")

print(data)

for i in range (0, len(data)):

    root.insert(data[i])

print(root.stringMethod(root))

print(root.find(root,5))

Program Screenshots

main.py 1~ class Node: 2 def _init_(self): 3 4 self.left = None self.right = None self.data = None 7 def _init_(self, data): 10 self.left 11 None self.right = None 12 self.data data 13 # Insert Node 14 def insert(self, data): 15 16 if self.data: 17 if data< self. data: if self.left is None: self.left = Node (data) 18 19 20 else: 21 self.left.insert(data) 22 elif data > self.data: if self.right is None: self.right = Node(data) else: 23 24 25 26 self.right.insert(data) 27 28 else: self.data 29 data 30 def stringMethod ( self, root) : 31 32 res=" if root.data is None: res ="Empty Tree" return res 33 34 35 else : 36

def stringMethod(self, root) : 31 32 res if root.data is None: res = "Empty Tree" return res 33 34 35 else: 36 +str(self.preorderTraversal(root)) + "\n" str(self.inorderTraversal(root)) +str(self.postorderTraversal(root)) + "\n". 37 "\nPreorder: res1 "Inorder: "+ "\n" 38 res2 "Postorder: ". 39 res3 40 res res1 res2 +res3 41 return res 42 43 def find(self, node, x): 44 45 if (node == None): return False 46 47 48 if (node.data == x): 49 50 return True 51 then recur on left subtree 52 res1 = self.find (node.left, x) 53 54 wnow recur on right subtree """ self.find(node.right, x) 55 56 res2 57 return res1 or res2 58 59 ***** Helper Methods ** ee * ************* 60 61 # Print the Tree 62 def PrintTree(self): if self.left: self.left.PrintTree () 63 64 65

**** He Lper Methods****** ****** 60 61 # Print the Tree 62 def Print Tree(self): if self.left: self.left.PrintTree () print( self.data), if self.right: self.right.PrintTree() 63 64 65 66 67 68 69 70 #Preorder traversal # Root -> Left -> Right def preorder Traversal(self, root): 71 72 73 t 74 res if root is not None: 75 +str(root.data)+ " ". +self.preorderTraversal(root.left) res + self.preorderTraversal(root.right) 76 res res 77 res res 78 = res 79 else: 80 res = res + 'N' + " " 81 82 return res 83 # Inorder traversal 84 # Left -> Root -> Right def inorderTraversal(self, root): res = " if root: 85 86 87 88 res +self.inorderTraversal(root.left) str(root.data) + " ". + self.inorderTraversal(root.right) 89 = res 90 res= res + 91 = res res else: 92 - 'N' + " ". 93 = res + res return res 94 95 # Postorder traversal 96

main.py 85 # Left -> Root -> Right def inorderTraversal(self, root): 86 87 res o if root: 88 res +self.inorderTraversal(root.left) str(root.data) + " ". self.inorder Traversal(root.right) 89 res = res + res =res + 90 91 else: 92 res = res + return res 93 N' + "" 94 95 # Postorder traversal 96 # Root -> Left -> Right def postorderTraversal(self, root): 97 98 99 res if root: res = res+ self. postorderTraversal(root.left) = res+ self.postorderTraversal(root.right) res = res +str(root.data) + " ". 100 101 102 res 103 else: 104 = res + 'N' + " * 105 res return res 106 107 108 print("Test Bed for Binary Search Tree Class") 109 test = input("Enter test Number (1-6): \n") 110 Node(None) [6, 8, 4, 3, 7, 5, 9] 111 root 112 data 113 print("Make a Balanced Tree.") 114 print("Inserting: ", end = " ") 115 print (data) 116 117- for i in range (0, len(data)): root.insert(data [ i] ) 118 119 120 print(root.stringMethod (root)) 121 print(root.find(root,5))

Program Output

Empty Tree with "find" method returning False.

120 121 print("Test Bed for Binary Search Tree Class") 122 test 123 root input("Enter test Number (1-6) :\n") Node(None) 124 125 print(root.stringMethod(root)) 126 print(root.find(root,5)) input Test Bed for Binary Search Tree Class Enter test Number (1-6): 2 Empty Tree False

Tree with data

120 121 print("Test Bed for Binary Search Tree Class") 122 test = input("Enter test Number (1-6) : \n") 123 Node(None) 124 root 125 data = [6, 8, 4, 3, 7, 5, 9] 126 print("Make 127 print("Inserting: ", end = " ") 128 print(data) a Balanced Tree.") 129 130 for i in range (0, len(data)): root.insert(data[i]) 131 132 133 print(root.stringMethod(root)) 134 print(root.find(root,5)) input Test Bed for Binary Search Tree class Enter test Number (1-6) : 2 Make a Balanced Tree. Inserting: [6, 8, 4, 3, 7, 5, 9] Preorder: 6 4 3 N N 5 N n 8 7 N N 9 Nn n Inorder: N 3 N 4 N 5 n 6 N 7 N 8 N 9 N Postorder: N N 3 N N 5 4 N N 7 N N 9 8 6 True .. Program finished with exit code 0 Press ENTER to exit console.