不二君

题目链接NN is an experienced internet user and that means he spends a lot of time on the social media. Once he found the following image on the Net, which asked him to compare the sizes of inner circles...

题目链接今年暑假杭电ACM集训队第一次组成女生队,其中有一队叫RPG,但做为集训队成员之一的野骆驼竟然不知道RPG三个人具体是谁谁。RPG给他机会让他猜猜，第一次猜：R是公主，P是草儿，G是月野兔；第二次猜：R是草儿，P是月野兔，G是公主；第三次猜：R是草儿，P是公主，G是月野兔；......可怜的野骆驼第六次终于把RPG分清楚了。由于RPG的带动，做ACM的女生越来越多，我们的野骆驼想都知道...

Codeforces Round #489 (Div. 2) B. Nastya Studies Informatics 题意：给出一个范围 l，r，两个数x，y。要求在【l，r】，找出一对a，b。使得gcd（a，b）=x，lcm（a，b）=y。问能找到多少对这样的数。题解：如果用a*b=x*y，肯定会超时。我们设a=n*x，b=x*m;就有，y=n*m*x，a*b=n*m*m*x;这样得...

In the Fibonacci integer sequence, F0 = 0, F1 = 1, and Fn = Fn − 1 + Fn − 2 for n ≥ 2. For example, the first ten terms of the Fibonacci sequence are:0, 1, 1, 2, 3, 5, 8, 13, 21, 34, …An alternati...

Fibsieve had a fantabulous (yes, it's an actual word) birthday party this year. He had so many gifts that he was actually thinking of not having a party next year.Among these gifts there was an N x ...