A. Shortest path of the king

It is very easy problem, but I wrote wrong direction and got 1 WA. Kanashisu...

B. Lorry

It is very easy problem too, but I confused the output specification. There's no example that has multiple vehicles numbers of output. I got many WAs. I was sad. I submitted many solutions that make small changes. Eventually I found the other mistake.

C. Tic-tac-toe

It is very easy problem too, but I miss a situation that fast won and first's move and vice versa are illegal. What a pity!

D. Least Cost Bracket Sequence

I complete to implement a divide and conqueror algorithm after the end, but I got TLE. I don't know a collect algorithm yet...