leetcode 1-Two Sum python
阿新 • • 發佈:2018-12-11
one-pass Hash Table
class Solution: def twoSum(self, nums, target): """ :type nums: List[int] :type target: int :rtype: List[int] """ d = {} for i in range(len(nums)): complement = target - nums[i] if(complement in d and d[complement] != i): return [d[complement], i] d[nums[i]] = i
d[nums[i]] = i 這條語句必須放在後面.因為當前元素的目標元素在dict中,若不在,當前元素再放入dict中.若放在前面可能出現當前元素和目標元素相等後,當前元素更新dict中目標元素,導致無解 如:[3,3]