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two_sum.pyPython · +12 more
1class Solution:2 def twoSum(self, nums, target):3 seen = {}4 for i, x in enumerate(nums):5 if target - x in seen:6 return [seen[target - x], i]7 seen[x] = i
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250 hand-verified problems
13 languages, one real judge
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250
verified problems
13
languages
3,100+
tests passing
Hand-verified problems, a real sandboxed judge, voice mock interviews, and spaced review — until it sticks.