[leetcode]两数之和

给定 nums = [2, 7, 11, 15], target = 9

因为 nums[0] + nums[1] = 2 + 7 = 9
所以返回 [0, 1]

class Solution(object):
def twoSum(self, nums, target):
"""
:type nums: List[int]
:type target: int
:rtype: List[int]
"""
nums_len = len(nums)
nums_dict={}
for i in range(0,len(nums)):
if nums[i] in nums_dict:
nums_dict[nums[i]].append(i)
else:
nums_dict[nums[i]]=[i]
for i in range(0,nums_len):
res=target-nums[i]
if res in nums_dict:
if nums[i] == res and len(nums_dict[res]) >= 2:
return [i, nums_dict[res][1]]
elif nums[i]!=res:
return [i,nums_dict[res][0]]