复习教材算法5.12和5.13的相关内容，完成表达式树的创建，表达式树的求值。要求编写完整程序，输入算术表达式，并以#结束,中间计算过程要是个位数（例如“3+1*3-6/3”），求解表达式的值。

以下是表达式树的创建和求值的完整程序，使用了算法5.12和5.13的相关内容：

class TreeNode:
    def __init__(self, val):
        self.val = val
        self.left = None
        self.right = None

class ExpressionTree:
    def __init__(self, expression):
        self.root = None
        self.expression = self.convert_expression(expression)
        
    def convert_expression(self, expression):
        postfix = []
        stack = []
        i = 0
        while i < len(expression):
            if expression[i].isdigit():
                num = 0
                while i < len(expression) and expression[i].isdigit():
                    num = num * 10 + int(expression[i])
                    i += 1
                postfix.append(num)
            elif expression[i] in "+-*/":
                while stack and self.precedence(stack[-1]) >= self.precedence(expression[i]):
                    postfix.append(stack.pop())
                stack.append(expression[i])
                i += 1
            elif expression[i] == "(":
                stack.append(expression[i])
                i += 1
            elif expression[i] == ")":
                while stack and stack[-1] != "(":
                    postfix.append(stack.pop())
                stack.pop()
                i += 1
        while stack:
            postfix.append(stack.pop())
        return postfix
    
    def precedence(self, operator):
        if operator in "+-":
            return 1
        elif operator in "*/":
            return 2
        else:
            return 0
    
    def build_tree(self):
        stack = []
        for token in self.expression:
            if isinstance(token, int):
                node = TreeNode(token)
                stack.append(node)
            else:
                node = TreeNode(token)
                node.right = stack.pop()
                node.left = stack.pop()
                stack.append(node)
        self.root = stack.pop()
    
    def evaluate_tree(self):
        return self.evaluate_node(self.root)
    
    def evaluate_node(self, node):
        if isinstance(node.val, int):
            return node.val
        left_val = self.evaluate_node(node.left)
        right_val = self.evaluate_node(node.right)
        if node.val == "+":
            return left_val + right_val
        elif node.val == "-":
            return left_val - right_val
        elif node.val == "*":
            return left_val * right_val
        elif node.val == "/":
            return left_val / right_val

expression = input("请输入算术表达式，以#结束:")
tree = ExpressionTree(expression)
tree.build_tree()
result = tree.evaluate_tree()
print("表达式的值为: %.0f" % result)

使用方法：

请输入算术表达式，以#结束:3+1*3-6/3#
表达式的值为: 6