本文共 1716 字，大约阅读时间需要 5 分钟。

题目：（困难）

标签：字符串、栈

解法一（栈）：

class Solution:    def parseBoolExpr(self, expression: str) -> bool:        stack = [[]]        i = 0        while i < len(expression):            ch = expression[i]            if ch == "!" or ch == "|" or ch == "&":                stack.append([ch])                i += 1            elif ch == ")":                now = stack.pop()                if now[0] == "!":                    tmp = not now[1]                elif now[0] == "&":                    tmp = all(now[1:])                else:                    tmp = any(now[1:])                stack[-1].append(tmp)            elif ch == "t":                stack[-1].append(True)            elif ch == "f":                stack[-1].append(False)            i += 1            # print(stack)        return stack[0][0]

解法二（将符号栈单独拆分）：

class Solution:    def parseBoolExpr(self, expression: str) -> bool:        mark_sign = []        stack = [[]]        for ch in expression:            if ch == "!" or ch == "|" or ch == "&":                mark_sign.append(ch)                stack.append([])            elif ch == ")":                mark = mark_sign.pop()                now = stack.pop()                if mark == "!":                    tmp = not now[0]                elif mark == "&":                    tmp = all(now)                else:                    tmp = any(now)                stack[-1].append(tmp)            elif ch == "t":                stack[-1].append(True)            elif ch == "f":                stack[-1].append(False)        return stack[0][0]

转载地址：https://dataartist.blog.csdn.net/article/details/108093411 如侵犯您的版权，请留言回复原文章的地址，我们会给您删除此文章，给您带来不便请您谅解！