Extend the buildParseTree function to handle mathematical expressions that do not have spaces between every character. Extend the buildParseTree function to handle mathematical expressions that do not have spaces between every character.

class Stack: def __init__(self): self.items = []

def isEmpty(self): return self.items == []

def push(self, item): self.items.append(item)

def pop(self): return self.items.pop()

def peek(self): return self.items[len(self.items)-1]

def size(self): return len(self.items)

class BinaryTree: """ A recursive implementation of Binary Tree Using links and Nodes approach. """ def __init__(self,rootObj): self.key = rootObj self.leftChild = None self.rightChild = None

def insertLeft(self,newNode): if self.leftChild == None: self.leftChild = BinaryTree(newNode) else: t = BinaryTree(newNode) t.left = self.leftChild self.leftChild = t def insertRight(self,newNode): if self.rightChild == None: self.rightChild = BinaryTree(newNode) else: t = BinaryTree(newNode) t.right = self.rightChild self.rightChild = t

def isLeaf(self): return ((not self.leftChild) and (not self.rightChild))

def getRightChild(self): return self.rightChild

def getLeftChild(self): return self.leftChild

def setRootVal(self,obj): self.key = obj

def getRootVal(self,): return self.key

def inorder(self): if self.leftChild: self.leftChild.inorder() print(self.key) if self.rightChild: self.rightChild.inorder()

def postorder(self): if self.leftChild: self.leftChild.postorder() if self.rightChild: self.rightChild.postorder() print(self.key)

def preorder(self): print(self.key) if self.leftChild: self.leftChild.preorder() if self.rightChild: self.rightChild.preorder()

def printexp(self): if self.leftChild: print('(', end=' ') self.leftChild.printexp() print(self.key, end=' ') if self.rightChild: self.rightChild.printexp() print(')', end=' ')

def postordereval(self): opers = {'+':operator.add, '-':operator.sub, '*':operator.mul, '/':operator.truediv} res1 = None res2 = None if self.leftChild: res1 = self.leftChild.postordereval() #// \label{peleft} if self.rightChild: res2 = self.rightChild.postordereval() #// \label{peright} if res1 and res2: return opers[self.key](res1,res2) #// \label{peeval} else: return self.key

def inorder(tree): if tree != None: inorder(tree.getLeftChild()) print(tree.getRootVal()) inorder(tree.getRightChild())

def printexp(tree): if tree.leftChild: print('(', end=' ') printexp(tree.getLeftChild()) print(tree.getRootVal(), end=' ') if tree.rightChild: printexp(tree.getRightChild()) print(')', end=' ')

def printexp(tree): sVal = "" if tree: sVal = '(' + printexp(tree.getLeftChild()) sVal = sVal + str(tree.getRootVal()) sVal = sVal + printexp(tree.getRightChild()) + ')' return sVal

def postordereval(tree): opers = {'+':operator.add, '-':operator.sub, '*':operator.mul, '/':operator.truediv} res1 = None res2 = None if tree: res1 = postordereval(tree.getLeftChild()) #// \label{peleft} res2 = postordereval(tree.getRightChild()) #// \label{peright} if res1 and res2: return opers[tree.getRootVal()](res1,res2) #// \label{peeval} else: return tree.getRootVal()

def height(tree): if tree == None: return -1 else: return 1 + max(height(tree.leftChild),height(tree.rightChild))

def buildParseTree(fpexp): fplist = fpexp.split() pStack = Stack() eTree = BinaryTree('') pStack.push(eTree) currentTree = eTree for i in fplist: if i == '(': currentTree.insertLeft('') pStack.push(currentTree) currentTree = currentTree.getLeftChild() elif i not in ['+', '-', '*', '/', ')']: currentTree.setRootVal(int(i)) parent = pStack.pop() currentTree = parent elif i in ['+', '-', '*', '/']: currentTree.setRootVal(i) currentTree.insertRight('') pStack.push(currentTree) currentTree = currentTree.getRightChild() elif i == ')': currentTree = pStack.pop() else: raise ValueError return eTree

pt = buildParseTree("( ( 10 + 5 ) * 3 )") pt.postorder()