CF980B.Marlin

普及/提高-

通过率:0%

AC君温馨提醒

该题目为【codeforces】题库的题目,您提交的代码将被提交至codeforces进行远程评测,并由ACGO抓取测评结果后进行展示。由于远程测评的测评机由其他平台提供,我们无法保证该服务的稳定性,若提交后无反应,请等待一段时间后再进行重试。

题目描述

The city of Fishtopia can be imagined as a grid of 44 rows and an odd number of columns. It has two main villages; the first is located at the top-left cell (1,1)(1,1) , people who stay there love fishing at the Tuna pond at the bottom-right cell (4,n)(4, n) . The second village is located at (4,1)(4, 1) and its people love the Salmon pond at (1,n)(1, n) .

The mayor of Fishtopia wants to place kk hotels in the city, each one occupying one cell. To allow people to enter the city from anywhere, hotels should not be placed on the border cells.

A person can move from one cell to another if those cells are not occupied by hotels and share a side.

Can you help the mayor place the hotels in a way such that there are equal number of shortest paths from each village to its preferred pond?

输入格式

The first line of input contain two integers, nn and kk ( 3n993 \leq n \leq 99 , 0k2×(n2)0 \leq k \leq 2\times(n-2) ), nn is odd, the width of the city, and the number of hotels to be placed, respectively.

输出格式

Print "YES", if it is possible to place all the hotels in a way that satisfies the problem statement, otherwise print "NO".

If it is possible, print an extra 44 lines that describe the city, each line should have nn characters, each of which is "#" if that cell has a hotel on it, or "." if not.

输入输出样例

  • 输入#1

    7 2
    

    输出#1

    YES
    .......
    .#.....
    .#.....
    .......
    
  • 输入#2

    5 3
    

    输出#2

    YES
    .....
    .###.
    .....
    .....
    
首页