{ "data": { "question": { "questionId": "287", "questionFrontendId": "287", "categoryTitle": "Algorithms", "boundTopicId": 1585, "title": "Find the Duplicate Number", "titleSlug": "find-the-duplicate-number", "content": "

Given an array of integers nums containing n + 1 integers where each integer is in the range [1, n] inclusive.

\n\n

There is only one repeated number in nums, return this repeated number.

\n\n

You must solve the problem without modifying the array nums and uses only constant extra space.

\n\n

 

\n

Example 1:

\n\n
\nInput: nums = [1,3,4,2,2]\nOutput: 2\n
\n\n

Example 2:

\n\n
\nInput: nums = [3,1,3,4,2]\nOutput: 3\n
\n\n

 

\n

Constraints:

\n\n\n\n

 

\n

Follow up:

\n\n\n", "translatedTitle": "寻找重复数", "translatedContent": "

给定一个包含 n + 1 个整数的数组 nums ,其数字都在 [1, n] 范围内(包括 1n),可知至少存在一个重复的整数。

\n\n

假设 nums 只有 一个重复的整数 ,返回 这个重复的数

\n\n

你设计的解决方案必须 不修改 数组 nums 且只用常量级 O(1) 的额外空间。

\n\n

 

\n\n

示例 1:

\n\n
\n输入:nums = [1,3,4,2,2]\n输出:2\n
\n\n

示例 2:

\n\n
\n输入:nums = [3,1,3,4,2]\n输出:3\n
\n\n

 

\n\n

提示:

\n\n\n\n

 

\n\n

进阶:

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