Answer to Question #260854 in Python for Jauani

Question

You are required to implement a simple symbolic equation solver. The equation must be stored in a binary tree.

Each operand or operator should be stored as a tuple of the form (TYPE, VALUE).

*the expression stored in the binary tree is“1+(2*3)+3^ 2"*

For example: (OPERAND, 5), (OPERAND, 7), (OPERATOR, '*’').

Following operators should be supported: addition (+), subtraction (-), multiplication (*), and exponentiation .

*Input*

root = Node(('OPERAND', 1))

root = root.insert(('OPERATOR', '+'), False)

root = root.insert(('OPERAND', 2), False)

root = root.insert(('OPERATOR', '*'), True)

root = root.insert(('OPERAND', 3), False)

root = root.insert(('OPERATOR', '+'), False)

root = root.insert(('OPERAND', 3), False)

root = root.insert(('OPERATOR', '^'), False)

root = root.insert(('OPERAND', 2), False)

root.get_output()

*Expected =* 100

(Should be print 100)

Answer 1

class Tree:
 def __init__(S, N=None):
     S.Q = []
     if N:
         S.Q.append(N)
         S.globalflag = False


 def E_node(S, N):
     if N.is_leaf:
       return float(N.value)
     elif N.value == '+':
       return S.E_node(N.left) + S.E_node(N.right)
     elif N.value == '-':
       return S.E_node(N.left) - S.E_node(N.right)
     elif N.value == '*':
       return S.E_node(N.left) * S.E_node(N.right)
     elif N.value == '^':
       return S.E_node(N.left) ** S.E_node(N.right)


 def event(S):
     while len(S.Q) > 1:
         S.Q[1].left = S.Q[0]
         S.Q[1].right = S.Q[2]
         S.Q.pop(2)
         S.Q.pop(0)


 def display(S):
     if len(S.Q) > 1:
       S.event()
       print(S.E_node(S.Q[0]))


 def insert(S, data, flag):
     if S.globalflag:
         S.Q[-1].right = Node(data)
         S.Q[-1].left = S.Q.pop(-2)
         S.globalflag = False
     else:
         S.globalflag = flag
         S.Q.append(Node(data))
     return S




class Node:
 def __init__(S, data, left=None, right=None):
     S.is_leaf = data[0] == 'OPERAND'
     S.value = data[1]
     S.left = left
     S.right = right


 def __repr__(S):
  return f'(value: {S.value}, left: {S.left}, right: {S.right})'




root = Tree(Node(('OPERAND', 1)))
root = root.insert(('OPERATOR', '+'), False)
root = root.insert(('OPERAND', 2), False)
root = root.insert(('OPERATOR', '*'), True)
root = root.insert(('OPERAND', 3), False)
root = root.insert(('OPERATOR', '+'), False)
root = root.insert(('OPERAND', 3), False)
root = root.insert(('OPERATOR', '^'), False)
root = root.insert(('OPERAND', 2), False)
root.display()