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: 1,2,3
:
-: 1, 2, 3, 1, 2, 3
-: 1, 1, 1, 2, 2, 2
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1999-001, 1999-002 2000-001, 2000-002...
AI-001, AI-002... HRW-001, HRW-002...
-001, -002 -001, -002..., -001
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