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two_sum.py · Structured traceSuccess · 14 steps

def two_sum(nums, target):
  seen = {}
  for i, num in enumerate(nums):
    complement = target - num
    if complement in seen:
      return [seen[complement], i]
    seen[num] = i

Step 09 · Complement match

Array state

211

315

nums[0] + nums[1] = target → [0, 1]

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