#586Medium#19 in American Express's list· asked at 16 companies
Find the Duplicate Number
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What we know
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 <= 10^5 - •
nums.length == n + 1 - •
1 <= nums[i] <= n - •
All the integers in
numsappear only once except for precisely one integer which appears two or more times.