Just can't find any mistake in my code... Maybe some tests will make it clear.

Edited by author 26.10.2014 01:50

try these tests, but i'm not sure it will help u

qwertyuiopasdfghjklzxcvb??
4

?a?a??a?
4

Edited by author 27.10.2014 19:36

try this test:

zyxx??
4

Answer: zyxxza