摘要：
Description A palindrome is a symmetrical string, that is, a string read identically from left to right as well as from right to left. Y... 阅读全文
摘要：
Vasya has n days of vacations! So he decided to improve his IT skills and do sport. Vasya knows the following information about each of thi... 阅读全文
摘要：
You’ve got a string s = s1s2… s|s| of length |s|, consisting of lowercase English letters. There also are q queries, each query is describe... 阅读全文
摘要：
Description ‘Oh no, they’ve done it again’, cries the chief designer at the Waferland chip factory. Once more the routing designers have... 阅读全文
摘要：
Description Bessie has gone to the mall’s jewelry store and spies a charm bracelet. Of course, she’d like to fill it with the best charm... 阅读全文