[LeetCode] 1. Two Sum_Easy

Posted 2020-11-19

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].

 1 class Solution(object):
 2     def twoSum(self, nums, target):
 3         """
 4         :type nums: List[int]
 5         :type target: int
 6         :rtype: List[int]
 7         """
 8          d =  {}
 9         for index, num in enumerate(nums):
10             if target -num in d:
11                 return [d[target-num], index]
12             d[num] = index
13         #return []      # 可以不要, 因为题目说肯定有一个solution