A - Fox And Snake

Problem description

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.

Input

The only line contains two integers: n and m (3 ≤ n, m ≤ 50).

n is an odd number.

Output

Output n lines. Each line should contain a string consisting of m characters. Do not output spaces.

Examples

Input

3 3

Output

###
..#
###

Input

3 4

Output

####
...#
####

Input

5 3

Output

###
..#
###
#..
###

Input

9 9

Output

#########
........#
#########
#........
#########
........#
#########
#........
#########
解题思路：按规律输出，当i为奇数时，输出的一行全部为'#'；当i为偶数时，用flag做开关，交换输出两种格式，水过！
AC代码：

 #include<bits/stdc++.h>
 using namespace std;
 #define FOR(a,b,c) for(int i=a;i<=b;++i)printf("%c",c)
 int n,m;bool flag;
 int main(){
     cin>>n>>m;flag=false;
     for(int i=;i<=n;++i){
         if(i%)FOR(,m,'#');
         else{
             if(!flag){FOR(,m-,'.');cout<<'#';flag=true;}
             else{cout<<'#';FOR(,m,'.');flag=false;}
         }
         cout<<endl;
     }
     return ;
 }