摘要：
Misha hacked the Codeforces site. Then he decided to let all the users change their handles. A user can now change his handle any numb... 阅读全文
摘要：
Most crossword puzzle fans are used to anagrams — groups of words with the same letters in differentorders — for example OPTS, SPOT, S... 阅读全文
摘要：
Leonid wants to become a glass carver (the person who creates beautiful artworks by cutting the glass). He already has a rectangular w... 阅读全文
摘要：
There is a bag-like data structure, supporting two operations:1 x Throw an element x into the bag.2 Take out an element from the bag.G... 阅读全文
摘要：
As the new term comes, the Ignatius Train Station is very busy nowadays. A lot of student want to get back to school by train(because ... 阅读全文
摘要：
Alice and Bob play 5-in-a-row game. They have a playing field of size 10 × 10. In turns they put either crosses or noughts, one at a t... 阅读全文
摘要：
Andy, 8, has a dream - he wants to produce hisvery own dictionary. This is not an easy task forhim, as the number of words that he kno... 阅读全文
摘要：
There are n pearls in a row. Let's enumerate them with integers from 1 to n from the left to the right. The pearl number i has the typ... 阅读全文
摘要：
You are given string s consists of opening and closing brackets of four kinds ,{}, [], (). There are two types of brackets: opening an... 阅读全文
摘要：
Now our hero finds the door to the BEelzebub feng5166. He opens the door and finds feng5166 is about to kill our pretty Princess. But ... 阅读全文