def build_parse_tree(fp_exp):
fp_list = fp_exp.split()
p_stack = Stack()
e_tree = BinaryTree('')
p_stack.push(e_tree)
current_tree = e_tree
for i in fp_list:
if i == '(':
current_tree.insert_left('')
p_stack.push(current_tree)
current_tree = current_tree.get_left_child()
elif i not in '+-*/)':
current_tree.set_root_val(int(i))
parent = p_stack.pop()
current_tree = parent
elif i in ['+', '-', '*', '/']:
current_tree.set_root_val(i)
current_tree.insert_right('')
p_stack.push(current_tree)
current_tree = current_tree.get_right_child()
elif i == ')':
current_tree = p_stack.pop()
else:
raise ValueError
return e_tree
def trans(deci, base):
flag = '0123456789ABCDEF'
stack = Stack()
while deci // base > 0:
stack.push(flag[deci % base])
deci //= base
stack.push(flag[deci])
print(stack.cstack)
from stackType_01 import Stack
while True:
stack = Stack()
str = input('input the arithmetic expression:')
if len(str) == 0:
print('input something')
else:
for i in str:
if i in '({[': #!!!
stack.push(i)
elif i in ')}]':
stack.pop()
if stack.size() == 0:
print('It is a balanced arithmetic expression')
else:
print('not a balanced arithmatic expression')
