A. Olesya and Rodion

time limit per test

1 second

memory limit per test

256 megabytes

input

standard input

output

standard output

Olesya loves numbers consisting of n digits, and Rodion only likes numbers that are divisible by t. Find some number that satisfies both of them.

Your task is: given the n and t print an …

有若干个活动，第i个开始时间和结束时间是[Si,fi)，同一个教室安排的活动之间不能交叠，求要安排所有活动，最少需要几个教室？

1第一行一个正整数n (n <= 10000)代表活动的个数。
2第二行到第(n + 1)行包含n个开始时间和结束时间。
3开始时间严格小于结束时间，并且时间都是非负整数，小于1000000000

输出

一行包含一个整数表示最少教室的个数。

输入示例

C. GCD Table

time limit per test

2 seconds

memory limit per test

256 megabytes

input

standard input

output

standard output

The GCD table G of size n × n for an array of positive integers a of length n is defined by formula

Let us remind you that the greatest common divisor (GCD) of two positive integers x …

sigh

也许今年不该参赛的….

因为暑假才刚刚调整好心态…

上学期基本废掉了…

感觉就是虚得不行，什么都不会的感觉….

B. Luxurious Houses

time limit per test

1 second

memory limit per test

256 megabytes

input

standard input

output

standard output

The capital of Berland has n multifloor buildings. The architect who built up the capital was very creative, so all the houses were built in one row.

Let’s enumerate all the houses from …

As I work with students I often face the situation when if a problem doesn’t seem clear to a student at the first sight, it makes them unable to solve it. Indeed, you always hear about specific methods and techniques. But you don’t hear about how to think in order to apply them. In this note I’ll try …

**序：**博弈是信息学和数学试题中常会出现的一种类型，算法灵活多变是其最大特点，而其中有一类试题更是完全无法用常见的博弈树来进行解答。 寻找必败态即为针对此类试题给出一种解题思路。

给６个矩形的长和宽（或者宽和长），问这六个矩形能否组成一个长方体．

思路比较简单，不过需要注意的地方有点多．

首先由于长和宽的顺序为止，所以要处理一下（一开始只处理了后来读入的五组，没有处理单独读入的第一组，差评）