Solution 1 from collections import defaultdict class Solution: #Solution 1 ''' Runtime: 67 ms, faster than 83.33% of Python3 online submissions for Two Sum. Memory Usage: 16.2 MB, less than 9.74% of Python3 online submissions for Two Sum. ''' def twoSum(self, nums: List[int], target: int) -> List[int]: dic = defaultdict(list) for idx, val in enumerate(nums): dic[val].append(idx) for idx, val in ..