Problem Description 给你一个高为n ，宽为m列的网格，计算出这个网格中有多少个矩形，下图为高为2，宽为4的网格.

Problem Description 给你N个整数,x1,x2…xn，任取两个整数组合得到|xi-xj|,(0 < i,j<=N,i!=j)。 现在请你计算第K大的组合数是哪个（一个组合数为第K大是指有K-1个不同的组合数小于它）。...

Problem Description 反素数就是满足对于任意i(0< i < x),都有g(i) < g(x),(g(x)是x的因子个数),则x为一个反素数。现在给你一个整数区间[a,b],请你求出该区间的x使g(x)最大。...

Problem Description lin2144是一只小菜鸟，都是笨鸟先飞，lin2144想来个菜鸟先飞，他从0点出发 一开始的飞行速度为1m/s，每过一个单位时间lin2144的飞行速

Problem Description 开学了，杭电又迎来了好多新生。ACMer想为新生准备一个节目。来报名要表演节目的人很多，多达N个，但是只需要从这N个人中选M个就够了，一共有多少种选择方法？...

Problem Description 给你2个分数，求他们的和，并要求和为最简形式。

Problem Description You are the CEO of Nasty Hacks Inc., a company that creates small pieces of malicious software which teenagers may use to fool their fri...

Problem Description The International Clown and Pierrot Competition (ICPC), is one of the most distinguished and also the most popular events on earth in the ...

Problem Description Roy has just moved into a new apartment. Well, actually the apartment itself is not very new, even dating back to the days before people h...

Problem Description A DFS(digital factorial sum) number is found by summing the factorial of every digit of a positive integer.