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我有一個問題，解析樹代碼。當我試圖用後期訂單展示它時，它給了我一個錯誤消息，應該是str參數，而不是int。[python-3] TypeError：必須是str，而不是int
from classStack import Stack
from classTree import BinaryTree
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("No se contempla el carácter evaluado")
return eTree
ParseTree = buildParseTree("(8 * 5)")
ParseTree.printPostordenTree(0)
錯誤：
Traceback (most recent call last):
File "C:\Users\Franco Calvacho\Downloads\Árboles\parseTree.py", line 38, in <module>
ParseTree.printPostordenTree(0)
File "C:\Users\Franco Calvacho\Downloads\Árboles\classTree.py", line 62, in printPostordenTree
self.getLeftChild().printPostordenTree(n+1)
File "C:\Users\Franco Calvacho\Downloads\Árboles\classTree.py", line 67, in printPostordenTree
print("Level: "+ str(n) + " " + self.getRootVal())
TypeError: must be str, not int
[Finished in 0.2s]
這裏的二叉樹代碼。我明確指出，BinaryTree代碼本身就可以，它不會給我那個錯誤信息。 在那個代碼下，我給你留下了python的評論，你可以看到。
class BinaryTree(object):
def __init__(self, data):
self.key = data
self.leftChild = None
self.rightChild = None
def insertLeft(self, newNode):
if self.leftChild == None:
self.leftChild = BinaryTree(newNode)
else:
t = BinaryTree(newNode)
t.leftChild = self.leftChild
self.leftChild = t
def insertRight(self, newNode):
if self.rightChild == None:
self.rightChild = BinaryTree(newNode)
else:
t = BinaryTree(newNode)
t.rightChild = self.rightChild
self.rightChild = t
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 printPreordenTree(self, n):
if self.getRootVal() != None:
print("Level: "+ str(n) + " " + self.getRootVal())
n+=1
if self.getLeftChild() != None:
self.getLeftChild().printPreordenTree(n)
if self.getRightChild() != None:
self.getRightChild().printPreordenTree(n)
return n
def printInordenTree(self, n):
if self.getRootVal() != None:
if self.getLeftChild() != None:
self.getLeftChild().printInordenTree(n+1)
print("Level: "+ str(n) + " " + self.getRootVal())
n+=1
if self.getRightChild() != None:
self.getRightChild().printInordenTree(n)
return n
def printPostordenTree(self, n):
if self.getRootVal() != None:
if self.getLeftChild() != None:
self.getLeftChild().printPostordenTree(n+1)
if self.getRightChild() != None:
self.getRightChild().printPostordenTree(n+1)
print("Level: "+ str(n) + " " + self.getRootVal())
n+=1
return n
"""a = BinaryTree("a")
a.insertLeft("b")
a.insertRight("c")
a.getLeftChild().insertLeft("d")
a.getRightChild().insertLeft("e")
a.getRightChild().insertRight("f")
print("Imprimo el árbol de forma Preorden")
a.printPreordenTree(0)
print("\nImprimo el árbol de forma Inorden")
a.printInordenTree(0)
print("\nImprimo el árbol de forma Postorden")
a.printPostordenTree(0)"""
可能的重複[在Python中使用字符串和整數生成字符串]（https://stackoverflow.com/questions/2823211/making-a-string-out-of-a-string-and-an -integer-in-python） –
'self.getRootVal（）'可能在違規行上返回一個int。 –
'currentTree.setRootVal（int（i））'將根設置爲一個整數。 'self.getRootVal（）'返回整數，如上面Jared所說。該bug可能首先將其設置爲整數，節點需要是字符串。 – Annan