{ "data": { "question": { "questionId": "2699", "questionFrontendId": "2563", "boundTopicId": null, "title": "Count the Number of Fair Pairs", "titleSlug": "count-the-number-of-fair-pairs", "content": "

Given a 0-indexed integer array nums of size n and two integers lower and upper, return the number of fair pairs.

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A pair (i, j) is fair if:

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Example 1:

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\nInput: nums = [0,1,7,4,4,5], lower = 3, upper = 6\nOutput: 6\nExplanation: There are 6 fair pairs: (0,3), (0,4), (0,5), (1,3), (1,4), and (1,5).\n
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Example 2:

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\nInput: nums = [1,7,9,2,5], lower = 11, upper = 11\nOutput: 1\nExplanation: There is a single fair pair: (2,3).\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 3.10.

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Kotlin 1.9.0.

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