{ "data": { "question": { "questionId": "1197", "questionFrontendId": "1106", "boundTopicId": null, "title": "Parsing A Boolean Expression", "titleSlug": "parsing-a-boolean-expression", "content": "

A boolean expression is an expression that evaluates to either true or false. It can be in one of the following shapes:

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Given a string expression that represents a boolean expression, return the evaluation of that expression.

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It is guaranteed that the given expression is valid and follows the given rules.

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Example 1:

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\nInput: expression = "&(|(f))"\nOutput: false\nExplanation: \nFirst, evaluate |(f) --> f. The expression is now "&(f)".\nThen, evaluate &(f) --> f. The expression is now "f".\nFinally, return false.\n
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Example 2:

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\nInput: expression = "|(f,f,f,t)"\nOutput: true\nExplanation: The evaluation of (false OR false OR false OR true) is true.\n
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Example 3:

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\nInput: expression = "!(&(f,t))"\nOutput: true\nExplanation: \nFirst, evaluate &(f,t) --> (false AND true) --> false --> f. The expression is now "!(f)".\nThen, evaluate !(f) --> NOT false --> true. We return true.\n
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Constraints:

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Compiled with clang 11 using the latest C++ 20 standard.

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Your code is compiled with level two optimization (-O2). AddressSanitizer is also enabled to help detect out-of-bounds and use-after-free bugs.

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Most standard library headers are already included automatically for your convenience.

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OpenJDK 17. Java 8 features such as lambda expressions and stream API can be used.

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Python 2.7.12.

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C# 10 with .NET 6 runtime

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Node.js 16.13.2.

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Some common data structure implementations are provided in the Algorithms module: https://www.rubydoc.info/github/kanwei/algorithms/Algorithms

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Python 3.10.

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