在构造二叉树时处理重复项

class TreeNode:
    def __init__(self, value):
        self.value = value
        self.count = 1  # 计数器
        self.left = None
        self.right = None

class BinaryTree:
    def __init__(self):
        self.root = None

    def insert(self, value):
        if not self.root:
            self.root = TreeNode(value)
        else:
            self._insert_recursive(self.root, value)

    def _insert_recursive(self, node, value):
        if value == node.value:
            node.count += 1  # 增加计数器
        elif value < node.value:
            if node.left is None:
                node.left = TreeNode(value)
            else:
                self._insert_recursive(node.left, value)
        else:
            if node.right is None:
                node.right = TreeNode(value)
            else:
                self._insert_recursive(node.right, value)

    def search(self, value):
        return self._search_recursive(self.root, value)

    def _search_recursive(self, node, value):
        if not node:
            return False
        if value == node.value:
            return True
        elif value < node.value:
            return self._search_recursive(node.left, value)
        else:
            return self._search_recursive(node.right, value)

# 示例用法
bt = BinaryTree()
bt.insert(5)
bt.insert(3)
bt.insert(7)
bt.insert(3)  # 重复值
print(bt.search(3))  # 输出: True
print(bt.search(4))  # 输出: False