{ "data": { "question": { "questionId": "287", "questionFrontendId": "287", "boundTopicId": null, "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.

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

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

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Example 1:

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

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

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Follow up:

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nums: List[int]) -> int:\n ", "__typename": "CodeSnippetNode" }, { "lang": "C", "langSlug": "c", "code": "int findDuplicate(int* nums, int numsSize) {\n \n}", "__typename": "CodeSnippetNode" }, { "lang": "C#", "langSlug": "csharp", "code": "public class Solution {\n public int FindDuplicate(int[] nums) {\n \n }\n}", "__typename": "CodeSnippetNode" }, { "lang": "JavaScript", "langSlug": "javascript", "code": "/**\n * @param {number[]} nums\n * @return {number}\n */\nvar findDuplicate = function(nums) {\n \n};", "__typename": "CodeSnippetNode" }, { "lang": "TypeScript", "langSlug": "typescript", "code": "function findDuplicate(nums: number[]): number {\n \n};", "__typename": "CodeSnippetNode" }, { "lang": "PHP", "langSlug": "php", "code": "class Solution {\n\n /**\n * @param Integer[] $nums\n * @return Integer\n */\n function findDuplicate($nums) {\n \n }\n}", "__typename": "CodeSnippetNode" }, { "lang": "Swift", "langSlug": "swift", "code": "class Solution {\n func findDuplicate(_ nums: 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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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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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