287. Find the Duplicate Number

Medium

30 Points

Array

Two Pointers

Binary Search

Bit Manipulation

Given an array of integers nums containing n + 1 integers where each integer is in the range [1, n] inclusive. There is only one repeated number in nums, return this repeated number. You must solve the problem without modifying the array nums and using only constant extra space.

Examples

Example 1

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

Example 2

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

Example 3

Input: nums = [3,3,3,3,3] Output: 3

Constraints

1 <= n <= 105
nums.length == n + 1
1 <= nums[i] <= n
All the integers in nums appear only once except for precisely one integer which appears two or more times.