C. Seat Arrangements time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Suppose that you are in a campus and have to go for classes day by day. As you may see, when you hurry to a classroom, y…

传送门:http://codeforces.com/contest/919/problem/C 给出一张n×m的座位表(有已占座位和空座位),请选择同一行(或列)内连续的k个座位.求选择的方法数. Hack:首先,若k=1,则所有的空座位均可选,方法数即为空座位数. 对于某一行(或列)中连续的len个座位,选择的方法数为len-k+1. 于是,分别逐行.逐列地统计,求出答案.参考程序如下: #include <stdio.h> #define MAX_N 2000 char map[MAX_N…

C. Seat Arrangements time limit per test1 second memory limit per test256 megabytes Problem Description Suppose that you are in a campus and have to go for classes day by day. As you may see, when you hurry to a classroom, you surprisingly find that…

C. Seat Arrangements   time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Suppose that you are in a campus and have to go for classes day by day. As you may see, when you hurry to a classroom,…

[链接] 我是链接,点我呀:) [题意] 在这里输入题意 [题解] 用pre[i][j]表示第i行前j列的和. 然后枚举连续座位的最左上点. (有两种可能向右或向下k个. 则还需要处理出pre2[i][j]表示第j列前i行的和. (都可以O(N^2)求出 然后pre[i][j+k-1]-pre[i][j-1]就是第i行第j列往右k个格子的空(或被占据)的格子数目了. 看看是不是符合要求就好. 往下扩展同理. k==1的时候只要取向右一种就好.所以直接除个2 [代码] #include <bits…

题目链接 \(Description\) 飞机上有n个位置.有m个乘客入座,每个人会从前门(1)或后门(n)先走到其票上写的位置.若该位置没人,则在这坐下:若该位置有人,则按原方向向前走直到找到空座坐下. 如果有人最后仍无座,he will be angry.求有多少种安排票上位置的方案使得没有人会angry(不同票写的位置可相同,从前门/后门进是不同的). \(Solution\) 如果我们添加一个位置到0或n+1,那么不合法情况就是有人坐在了这个位置. 那么加入n+1后,可以把序列看成环,这…

A. Supermarket We often go to supermarkets to buy some fruits or vegetables, and on the tag there prints the price for a kilo. But in some supermarkets, when asked how much the items are, the clerk will say that a yuan for b kilos (You don't need to…

Spies Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/gym/100463/attachments Description In the aftermath of Canada’s annexation of Pittsburgh tensions have been pretty high between Canada and the US. You have personally been hired…

B. Food on the Plane time limit per test:2 seconds memory limit per test:256 megabytes input:standard input output:standard output A new airplane SuperPuperJet has an infinite number of rows, numbered with positive integers starting with 1 from cockp…

B. Game of the Rows time limit per test:1 second memory limit per test:256 megabytes input:standard input output:standard output Daenerys Targaryen has an army consisting of k groups of soldiers, the i-th group contains ai soldiers. She wants to brin…