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简况

总结与反思

cmx

lpy

xsy

题解

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. Stairs of Tetris

J. Pairs

K. Lying Island

补题