Two-Sum Leetcodes problem L1

two-sum problem

https://leetcode.com/problems/two-sum/

my solution

class Solution(object):
    def twoSum(self, nums, target):
        d = {}
        for i in range(len(nums)):
            if nums[i] in d:
                d[nums[i]].append(i)
            else: 
                d[nums[i]] = [i]
        for k in d:
            a = d[k].pop()
            b = target - nums[a]
            if b in d:
                if d[b]:
                    return [a,d[b].pop()]
            else:
                d[k].append(a)

I solved the problem using a dictionary. I set the keys as the values in the list.

Then I appended index of the values in the list into the list in the key of the dictionary.

This way, I can account for the duplicate values by popping each value out of the list in the dictionary.

Runtime: 52 ms, faster than 58.15% of Python online submissions for Two Sum.

Memory Usage: 15.2 MB, less than 6.34% of Python online submissions for Two Sum.

However, I barely made it past 50% of the submissions score.

best solution

class Solution(object):
    def twoSum(self, nums, target):
        hashMap={nums[idx]:idx for idx in range(len(nums))} # {num : index}        
        for idx in range(len(nums)):
            complement=target-nums[idx]
            if hashMap.get(complement,False) and hashMap.get(complement,False) != idx:
                return [idx,hashMap.get(complement)]              

Runtime: 40 ms, faster than 92.58% of Python online submissions for Two Sum.

Memory Usage: 14.4 MB, less than 23.67% of Python online submissions for Two Sum.

I guess I still have to learn how tto use pythonic coding.