Mush Takahashi learn these skills in order?
e.g.
if input:
5
0 0
2 2
5 4
0 0
2 2
is the output 3 (skills 1,3,4) or 2 (at the time you learn skill 3 you have no idea what skill 4 is)?

The skills can be learned in any order. / スキルは好きな順序で習得することができます。