{ "data": { "question": { "questionId": "3299", "questionFrontendId": "3020", "categoryTitle": "Algorithms", "boundTopicId": 2619046, "title": "Find the Maximum Number of Elements in Subset", "titleSlug": "find-the-maximum-number-of-elements-in-subset", "content": "

You are given an array of positive integers nums.

\n\n

You need to select a subset of nums which satisfies the following condition:

\n\n\n\n

Return the maximum number of elements in a subset that satisfies these conditions.

\n\n

 

\n

Example 1:

\n\n
\nInput: nums = [5,4,1,2,2]\nOutput: 3\nExplanation: We can select the subset {4,2,2}, which can be placed in the array as [2,4,2] which follows the pattern and 22 == 4. Hence the answer is 3.\n
\n\n

Example 2:

\n\n
\nInput: nums = [1,3,2,4]\nOutput: 1\nExplanation: We can select the subset {1}, which can be placed in the array as [1] which follows the pattern. Hence the answer is 1. Note that we could have also selected the subsets {2}, {4}, or {3}, there may be multiple subsets which provide the same answer. \n
\n\n

 

\n

Constraints:

\n\n\n", "translatedTitle": "子集中元素的最大数量", "translatedContent": "

给你一个 正整数 数组 nums 。

\n\n

你需要从数组中选出一个满足下述条件的子集：

\n\n\n\n

返回满足这些条件的子集中，元素数量的 最大值 。

\n\n

 

\n\n

示例 1：

\n\n
\n输入：nums = [5,4,1,2,2]\n输出：3\n解释：选择子集 {4,2,2} ，将其放在数组 [2,4,2] 中，它遵循该模式，且 22 == 4 。因此答案是 3 。\n
\n\n

示例 2：

\n\n
\n输入：nums = [1,3,2,4]\n输出：1\n解释：选择子集 {1}，将其放在数组 [1] 中，它遵循该模式。因此答案是 1 。注意我们也可以选择子集 {2} 、{4} 或 {3} ，可能存在多个子集都能得到相同的答案。\n
\n\n

 

\n\n

提示：

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