Essential LeetCode Problems with Optimized Solutions
Two Sum
Use a hash map to store each number’s index. For every element, check if the complement (target - current) exists in the map.
class Solution:
def twoSum(self, nums: List[int], target: int) -> List[int]:
seen = {}
for idx, val in enumerate(nums):
complement = target - val
if complement in se ...
Posted on Wed, 08 Jul 2026 17:19:04 +0000 by xeidor