A9862. Fox And Snake
编程题
普及/提高-
知识点
题目描述
Fox Ciel starts to learn programming. The first task is drawing a fox! However, that turns out to be too hard for a beginner, so she decides to draw a snake instead.
A snake is a pattern on a $n$ by $m$ table. Denote $c$ -th cell of $r$ -th row as $(r,c)$ . The tail of the snake is located at $(1,1)$ , then it's body extends to $(1,m)$ , then goes down $2$ rows to $(3,m)$ , then goes left to $(3,1)$ and so on.
Your task is to draw this snake for Fox Ciel: the empty cells should be represented as dot characters ('.') and the snake cells should be filled with number signs ('\#').
Consider sample tests in order to understand the snake pattern.
A snake is a pattern on a $n$ by $m$ table. Denote $c$ -th cell of $r$ -th row as $(r,c)$ . The tail of the snake is located at $(1,1)$ , then it's body extends to $(1,m)$ , then goes down $2$ rows to $(3,m)$ , then goes left to $(3,1)$ and so on.
Your task is to draw this snake for Fox Ciel: the empty cells should be represented as dot characters ('.') and the snake cells should be filled with number signs ('\#').
Consider sample tests in order to understand the snake pattern.
输入格式
The only line contains two integers: $n$ and $m$ ( $3<=n,m<=50$ ).
$n$ is an odd number.
$n$ is an odd number.
输出格式
Output $n$ lines. Each line should contain a string consisting of $m$ characters. Do not output spaces.
输入输出样例
输入 #1
3 3
输出 #1
### ..# ###
输入 #2
3 4
输出 #2
#### ...# ####
输入 #3
5 3
输出 #3
### ..# ### #.. ###
输入 #4
9 9
输出 #4
######### ........# ######### #........ ######### ........# ######### #........ #########