| 1 | 两数之和 | 一开始用首尾递进查找做的，需要一次排序，时间复杂度是 O(nlogn)，下面是 Python3 代码：
class Solution:
def twoSum(self, nums, target):
"""
:type nums: List[int]
:type target: int
:rtype: List[int]
"""
sorted_id = sorted(range(len(nums)), key=lambda k: nums[k])
head = 0
tail = len(nums) - 1
sum_result = nums[sorted_id[head]] + nums[sorted_id[tail]]
while sum_result != target:
if sum_result > target:
tail -= 1
elif sum_result < target:
head += 1
sum_result = nums[sorted_id[head]] + nums[sorted_id[tail]]
return [sorted_id[head], sorted_id[tail]]
| 后来看解答发现可以用字典做，时间复杂度是 O(n)，还是太年轻： | Mar 15, 2019, 10:49:23 AM |
