from pythonds.basic import Stack
from pythonds.trees import BinaryTree
def buiildParseTree(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(eval(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("Unknown Operator: " + i)
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