令$d=\gcd(n,m)$,存在$x$和$y$使得$xn+i=ym+j$的充要条件是$i\equiv j(mod \ d)$,因此将$xd+i$(其中$0\le i<d$)作为一组,共有$d$组,根据上述结论任意两组之间相互独立 若一组中没有快乐的人,由于独立性必然无解,即有解需要$且\forall 0\le i<d,\exists t\in x\cup y且t\equiv i(mod\ d)$,必要条件为$d\le b+g$(以下记$b+g$为$N$来表示复杂度),因此可以对每一组分别求出…

C. Drazil and Factorial time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Drazil is playing a math game with Varda. Let's define for positive integer x as a product of factorials of its digi…

B. Drazil and His Happy Friends time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Drazil has many friends. Some of them are happy and some of them are unhappy. Drazil wants to make all his f…

C. Drazil and Park 题目连接: http://codeforces.com/contest/516/problem/C Description Drazil is a monkey. He lives in a circular park. There are n trees around the park. The distance between the i-th tree and (i + 1)-st trees is di, the distance between t…

B. Drazil and Tiles 题目连接: http://codeforces.com/contest/516/problem/B Description Drazil created a following problem about putting 1 × 2 tiles into an n × m grid: "There is a grid with some cells that are empty and some cells that are occupied. You s…

[codeforces 516]A. Drazil and Factorial 试题描述 Drazil is playing a math game with Varda. Let's define  for positive integer x as a product of factorials of its digits. For example, . First, they choose a decimal number a consisting of n digits that con…

Drazil and Factorial time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Drazil is playing a math game with Varda. Let's define  for positive integer x as a product of factorials of its digits…

Drazil and His Happy Friends time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Drazil has many friends. Some of them are happy and some of them are unhappy. Drazil wants to make all his frie…

Drazil and Date time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Someday, Drazil wanted to go on date with Varda. Drazil and Varda live on Cartesian plane. Drazil's home is located in point …

B. Drazil and Tiles   Drazil created a following problem about putting 1 × 2 tiles into an n × m grid: "There is a grid with some cells that are empty and some cells that are occupied. You should use 1 × 2 tiles to cover all empty cells and no two ti…