LC 0136 [E] Single Number - ALawliet/algorithms GitHub Wiki
class Solution:
def singleNumber(self, nums: List[int]) -> int:
# O(n), O(n)
freqs = Counter(nums)
for num, freq in freqs.items():
if freq == 1:
return num
def singleNumber(self, nums: List[int]) -> int:
# O(n), O(1)
a = 0
for i in nums:
a ^= i
return a