OJ Board

Problems:
http://neerc.ifmo.ru/subregions/northern/problems.pdf

and official test cases:
http://neerc.ifmo.ru/subregions/northern/tests.rar
in this file also has check.exe which is check your answer

after the constest i soved all problem, which i couldn't solved during the contest, except one.

First problem Alphabet, could any one will try two solve this one.
if you solve, please share me your algo.

thanks.

problem Alphabet, have anyone interested with this problem, i think it is a np-complete.