摘要：
The round carousel consists of nn figures of animals. Figures are numbered from 11 to nn in order of the carousel moving. Thus, after the nn -th figur 阅读全文
摘要：
A number is ternary if it contains only digits 00 , 11 and 22 . For example, the following numbers are ternary: 10221022 , 1111 , 2121 , 20022002 . Yo 阅读全文
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For the given integer nn (n>2n>2 ) let's write down all the strings of length nn which contain n−2n−2 letters 'a' and two letters 'b' in lexicographic 阅读全文
摘要：
You are given two positive integers aa and bb. In one move you can increase aa by 11 (replace aa with a+1a+1). Your task is to find the minimum number 阅读全文