{ "data": { "question": { "questionId": "646", "questionFrontendId": "646", "boundTopicId": null, "title": "Maximum Length of Pair Chain", "titleSlug": "maximum-length-of-pair-chain", "content": "

You are given an array of n pairs pairs where pairs[i] = [lefti, righti] and lefti < righti.

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A pair p2 = [c, d] follows a pair p1 = [a, b] if b < c. A chain of pairs can be formed in this fashion.

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Return the length longest chain which can be formed.

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You do not need to use up all the given intervals. You can select pairs in any order.

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Example 1:

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\nInput: pairs = [[1,2],[2,3],[3,4]]\nOutput: 2\nExplanation: The longest chain is [1,2] -> [3,4].\n
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Example 2:

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\nInput: pairs = [[1,2],[7,8],[4,5]]\nOutput: 3\nExplanation: The longest chain is [1,2] -> [4,5] -> [7,8].\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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