1
n, m = map(int, input().split())
2
table = [['.' for j in range(m)] for i in range(n)]
3
 
4
for i in range(n):
5
    if i % 2 == 0:
6
        for j in range(m):
7
            table[i][j] = '#'
8
    else:
9
        if (i // 2) % 2 == 0:
10
            table[i][m - 1] = '#'
11
        else:
12
            table[i][0] = '#'
13
            
14
for row in table:
15
    for cell in row:
16
        print(cell, end='')
17
    print()