Required Mahjong Tiles

A puzzle app using mahjong tiles. 
Touch the required mahjong tiles to win with flush. 
In "Practice" mode, you can see the answer of each question.
In "Time Attack" mode, your score is recorded in the Game Center.

Points:
with Full Flush
Not Tenpai…..10pt
Number of required tiles is less than 3…..10pt/tile
3-4…..15pt/tile
more than 4…..20pt/tile

with Half Flush
Not Tenpai…..5pt
Number of required tiles is less than 3…..5pt/tile
3-4…..10pt/tile
more than 4…..15pt/tile

Wrong Answer…..-10pt