{ "data": { "question": { "questionId": "983", "questionFrontendId": "946", "boundTopicId": null, "title": "Validate Stack Sequences", "titleSlug": "validate-stack-sequences", "content": "

Given two integer arrays pushed and popped each with distinct values, return true if this could have been the result of a sequence of push and pop operations on an initially empty stack, or false otherwise.

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Example 1:

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\nInput: pushed = [1,2,3,4,5], popped = [4,5,3,2,1]\nOutput: true\nExplanation: We might do the following sequence:\npush(1), push(2), push(3), push(4),\npop() -> 4,\npush(5),\npop() -> 5, pop() -> 3, pop() -> 2, pop() -> 1\n
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Example 2:

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\nInput: pushed = [1,2,3,4,5], popped = [4,3,5,1,2]\nOutput: false\nExplanation: 1 cannot be popped before 2.\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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Python 3.10.

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