Leetcode 1106. Parsing A Boolean Expression

文章作者：Tyan
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1. Description

2. Solution

**解析：**Version 1，使用栈来求解，当碰到逻辑运算、(以及操作数时，入栈，当每次碰到)时，先将操作数出栈，然后再将逻辑运算出栈，计算逻辑运算的结果，将结果压入栈中，最终，栈中只剩下最终结果。

• Version 1

class Solution:def parseBoolExpr(self, expression: str) -> bool:operations = []for i in range(len(expression)):if expression[i] == '&' or expression[i] == '|' or expression[i] == '!' or expression[i] == '(':operations.append(expression[i])elif expression[i] == 't':operations.append(True)elif expression[i] == 'f':operations.append(False)elif expression[i] == ')':operators = []while operations[-1] != '(':operators.append(operations.pop(-1))operations.pop(-1)logic = operations.pop(-1)if logic == '&':temp = Truefor val in operators:temp &= valelif logic == '|':temp = False for val in operators:temp |= valelse:temp = not operators[-1]operations.append(temp)return operations[-1]

Reference

1. https://leetcode.com/problems/parsing-a-boolean-expression/