Problem:
Print a Frame

Draw a frame which has a height of H cm and a width of W cm. For example, the following figure shows a frame which has a height of 6 cm and a width of 10 cm.

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

Input

The input consists of multiple datasets. Each dataset consists of two integers H and W separated by a single space.

The input ends with two 0 (when both H and W are zero).

Output

For each dataset, print the frame made of '#' and '.'.

Print a blank line after each dataset.

Constraints

3 ≤ H ≤ 300

3 ≤ W ≤ 300

Sample Input

3 4
5 6
3 3
0 0

Sample Output

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

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

###
#.#
###

Solution in Python3 (judge verdict: Accepted)

while True:
    a,b = map(int,input().split())
    if a == 0 and b == 0: break
    for i in range(a):
        for j in range(b):
            if j == 0 or j == b-1 or i == 0 or i == a -1:
                print(r"#",end="")
            else:
                print(r".",end="")
        print()
    print("")