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Medium

Array

Find the Duplicate Number

Examples

Input: nums = [1,3,4,2,2]

Output: 2

Sample Test Cases

Case 1 Input: [1,3,4,2,2]

Expected: 2

Case 2 Input: [3,1,3,4,2]

Expected: 3

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Case 1 Input: [1,3,4,2,2]

Expected: 2

Case 2 Input: [3,1,3,4,2]

Expected: 3

An array nums of n+1 integers in [1,n] has exactly one duplicate. Find it without modifying the array and using O(1) extra space.