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:
    x=input().split()
    a=int(x[0])
    b=int(x[1])
    c=a-2
    d=b-2
    if a ==0 and b==0:
        break
    print("#"*b)
    for i in range(c):
        print("#"+"."*d+"#")
    print("#"*b)
    print("")