{ "data": { "question": { "questionId": "150", "questionFrontendId": "150", "boundTopicId": null, "title": "Evaluate Reverse Polish Notation", "titleSlug": "evaluate-reverse-polish-notation", "content": "

Evaluate the value of an arithmetic expression in Reverse Polish Notation.

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Valid operators are +, -, *, and /. Each operand may be an integer or another expression.

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Note that division between two integers should truncate toward zero.

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It is guaranteed that the given RPN expression is always valid. That means the expression would always evaluate to a result, and there will not be any division by zero operation.

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Example 1:

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\nInput: tokens = ["2","1","+","3","*"]\nOutput: 9\nExplanation: ((2 + 1) * 3) = 9\n
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Example 2:

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\nInput: tokens = ["4","13","5","/","+"]\nOutput: 6\nExplanation: (4 + (13 / 5)) = 6\n
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Example 3:

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\nInput: tokens = ["10","6","9","3","+","-11","*","/","*","17","+","5","+"]\nOutput: 22\nExplanation: ((10 * (6 / ((9 + 3) * -11))) + 17) + 5\n= ((10 * (6 / (12 * -11))) + 17) + 5\n= ((10 * (6 / -132)) + 17) + 5\n= ((10 * 0) + 17) + 5\n= (0 + 17) + 5\n= 17 + 5\n= 22\n
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Constraints:

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C# 10 with .NET 6 runtime

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