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1001. N Repeated Element In Size 2n Array

Array Hash Table

Problem - N Repeated Element In Size 2n Array

Easy

You are given an integer array nums with the following properties:

  • nums.length == 2 * n.
  • nums contains n + 1 unique elements.
  • Exactly one element of nums is repeated n times.

Return the element that is repeated n times.

 

Example 1:

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

Example 2:

Input: nums = [2,1,2,5,3,2]
Output: 2

Example 3:

Input: nums = [5,1,5,2,5,3,5,4]
Output: 5

 

Constraints:

  • 2 <= n <= 5000
  • nums.length == 2 * n
  • 0 <= nums[i] <= 104
  • nums contains n + 1 unique elements and one of them is repeated exactly n times.

Solutions

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class Solution:
    def repeatedNTimes(self, nums: List[int]) -> int:
        # n = len(nums) // 2
        # count = Counter(nums)

        # for val, cnt in count.items():
        #     if cnt == n:
        #         return val
        vis = set()
        for i in nums:
            if i in vis:
                return i
            vis.add(i)

Submission Stats:

  • Runtime: 0 ms (100.00%)
  • Memory: 18.4 MB (98.97%)