HDU-3335 Divisibility

04-02

HDU-4069 Squiggly Sudoku

03-31

ZOJ-3122 Sudoku

03-27

POJ-3074 Sudoku

03-27

POJ-1084 Square Destroyer

03-27

FZU-1686 神龙的难题

03-19

HDU-2295 Radar

03-19

ZOJ-1017 Treasure Map

03-16

HUST-1017 Exact cover

03-10