seen [terminology]

Terminology¶

Usage¶

• Use for values, states, keys, or remainders encountered before.
• It commonly supports:
  • Duplicate detection
  • Cycle detection in generated states
  • Recurring-decimal detection
  • Value-to-position lookup
• It does not necessarily imply that a graph node has been fully processed.

seen = set()

for x in nums:
    if x in seen:
        return True
    seen.add(x)