{ "data": { "question": { "questionId": "1667", "questionFrontendId": "1545", "boundTopicId": null, "title": "Find Kth Bit in Nth Binary String", "titleSlug": "find-kth-bit-in-nth-binary-string", "content": "

Given two positive integers n and k, the binary string Sn is formed as follows:

\n\n\n\n

Where + denotes the concatenation operation, reverse(x) returns the reversed string x, and invert(x) inverts all the bits in x (0 changes to 1 and 1 changes to 0).

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For example, the first four strings in the above sequence are:

\n\n\n\n

Return the kth bit in Sn. It is guaranteed that k is valid for the given n.

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Example 1:

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\nInput: n = 3, k = 1\nOutput: "0"\nExplanation: S3 is "0111001".\nThe 1st bit is "0".\n
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Example 2:

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\nInput: n = 4, k = 11\nOutput: "1"\nExplanation: S4 is "011100110110001".\nThe 11th bit is "1".\n
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Constraints:

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