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AC 7题,Rank 9th
A. Is Your System Safe?
B. Tiling Dominoes
C. Skating on Weiming Lake
D. Travel to Qomolangma
E. Walking Around the Country
F. A Simple Math Problem
G. Go! Go! Go!
H. Reverse K-th Problem
I. Lying Island
J. Stairs of Tetris
K. Pairs