{ "data": { "question": { "questionId": "1907", "questionFrontendId": "1803", "boundTopicId": null, "title": "Count Pairs With XOR in a Range", "titleSlug": "count-pairs-with-xor-in-a-range", "content": "

Given a (0-indexed) integer array nums and two integers low and high, return the number of nice pairs.

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A nice pair is a pair (i, j) where 0 <= i < j < nums.length and low <= (nums[i] XOR nums[j]) <= high.

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Example 1:

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\r\nInput: nums = [1,4,2,7], low = 2, high = 6\r\nOutput: 6\r\nExplanation: All nice pairs (i, j) are as follows:\r\n    - (0, 1): nums[0] XOR nums[1] = 5 \r\n    - (0, 2): nums[0] XOR nums[2] = 3\r\n    - (0, 3): nums[0] XOR nums[3] = 6\r\n    - (1, 2): nums[1] XOR nums[2] = 6\r\n    - (1, 3): nums[1] XOR nums[3] = 3\r\n    - (2, 3): nums[2] XOR nums[3] = 5\r\n
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Example 2:

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\r\nInput: nums = [9,8,4,2,1], low = 5, high = 14\r\nOutput: 8\r\nExplanation: All nice pairs (i, j) are as follows:\r\n​​​​​    - (0, 2): nums[0] XOR nums[2] = 13\r\n    - (0, 3): nums[0] XOR nums[3] = 11\r\n    - (0, 4): nums[0] XOR nums[4] = 8\r\n    - (1, 2): nums[1] XOR nums[2] = 12\r\n    - (1, 3): nums[1] XOR nums[3] = 10\r\n    - (1, 4): nums[1] XOR nums[4] = 9\r\n    - (2, 3): nums[2] XOR nums[3] = 6\r\n    - (2, 4): nums[2] XOR nums[4] = 5
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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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C# 10 with .NET 6 runtime

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Node.js 16.13.2.

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Ruby 3.1

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Swift 5.5.2.

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Go 1.21

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Python 3.10.

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Scala 2.13.7.

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Kotlin 1.9.0.

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Rust 1.58.1

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With bcmath module

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