竞赛problems
............\BAOGAO.doc
............\problem_doc
............\...........\A.doc
............\...........\B.doc
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............\...........\D.doc
............\...........\E.doc
............\...........\F.doc
............\...........\G.doc
............\...........\H.doc
............\...........\I.doc
............\problem_pdf
............\...........\A.pdf
............\...........\B.pdf
............\...........\C.pdf
............\...........\D.pdf
............\...........\E.pdf
............\...........\F.pdf
............\...........\G.pdf
............\...........\H.pdf
............\...........\I.pdf