Leetcode 001-twosum

 #Given an array of integers, return indices of the two numbers such that they add up to a specific target.
 #You may assume that each input would have exactly one solution, and you may not use the same element twice.
 #Example:
 #Given nums = [2, 7, 11, 15], target = 9,
 #Because nums[0] + nums[1] = 2 + 7 = 9,
 #return [0, 1].
 def twoSum(nums, target):
     dic = dict()
     for index,value in enumerate(nums):
         sub = target - value
         if sub in dic:
             return [dic[sub],index]
         else:
             dic[value] = index
 L=[1,2,3,5]
 print(twoSum(L,7))

这道题的解题思路很简单，利用python中的字典记录记录下每个元素出现的位置，也就是其他语言中的哈希表。