{ "data": { "question": { "questionId": "3081", "questionFrontendId": "2856", "boundTopicId": null, "title": "Minimum Array Length After Pair Removals", "titleSlug": "minimum-array-length-after-pair-removals", "content": "

You are given a 0-indexed sorted array of integers nums.

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You can perform the following operation any number of times:

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Return an integer that denotes the minimum length of nums after performing the operation any number of times (including zero).

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Note that nums is sorted in non-decreasing order.

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Example 1:

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\nInput: nums = [1,3,4,9]\nOutput: 0\nExplanation: Initially, nums = [1, 3, 4, 9].\nIn the first operation, we can choose index 0 and 1 because nums[0] < nums[1] <=> 1 < 3.\nRemove indices 0 and 1, and nums becomes [4, 9].\nFor the next operation, we can choose index 0 and 1 because nums[0] < nums[1] <=> 4 < 9.\nRemove indices 0 and 1, and nums becomes an empty array [].\nHence, the minimum length achievable is 0.
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Example 2:

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\nInput: nums = [2,3,6,9]\nOutput: 0\nExplanation: Initially, nums = [2, 3, 6, 9]. \nIn the first operation, we can choose index 0 and 2 because nums[0] < nums[2] <=> 2 < 6. \nRemove indices 0 and 2, and nums becomes [3, 9]. \nFor the next operation, we can choose index 0 and 1 because nums[0] < nums[1] <=> 3 < 9. \nRemove indices 0 and 1, and nums becomes an empty array []. \nHence, the minimum length achievable is 0.\n
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Example 3:

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\nInput: nums = [1,1,2]\nOutput: 1\nExplanation: Initially, nums = [1, 1, 2].\nIn an operation, we can choose index 0 and 2 because nums[0] < nums[2] <=> 1 < 2. \nRemove indices 0 and 2, and nums becomes [1]. \nIt is no longer possible to perform an operation on the array. \nHence, the minimum achievable length is 1. \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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Most standard library headers are already included automatically for your convenience.

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Includes Pair class from https://docs.oracle.com/javase/8/javafx/api/javafx/util/Pair.html.

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Python 2.7.12.

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Go 1.21

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