Description
In a array A of size 2N, there are N+1 unique elements, and exactly one of these elements is repeated N times.
Return the element repeated N times.
在大小为 2N 的数组 A 中有 N+1 个不同的元素，其中有一个元素重复了 N 次。
返回重复了 N 次的那个元素。
题目链接：https://leetcode.com/problems/n-repeated-element-in-size-2n-array
Difficulty: easy
Example 1:
Input: [1,2,3,3]
Output: 3
Example 2:
Input: [2,1,2,5,3,2]
Output: 2
Example 3:
Input: [5,1,5,2,5,3,5,4]
Output: 5
Note:
- 4 <= A.length <= 10000
- 0 <= A[i] < 10000
- A.length is even
分析
- updating
参考代码
class Solution:
def repeatedNTimes(self, A):
D=set()
for a in A:
if(a not in D):
D.add(a)
else:
return a
return