括号匹配python

括号匹配是一个常见的问题，可以使用栈来解决。下面是一个用Python实现括号匹配的示例代码：

def is_balanced(expression):
    stack = []
    opening_brackets = ['(', '[', '{']
    closing_brackets = [')', ']', '}']
    
    for char in expression:
        if char in opening_brackets:
            stack.append(char)
        elif char in closing_brackets:
            if len(stack) == 0:
                return False
            top_char = stack.pop()
            if opening_brackets.index(top_char) != closing_brackets.index(char):
                return False
    
    return len(stack) == 0

# 测试
expression = input("请输入待检测的表达式：")
if is_balanced(expression):
    print("括号匹配成功！")
else:
    print("括号匹配失败！")

请注意，上述代码只能检测括号是否匹配，而不能检测其他符号如方括号、花括号等是否匹配。