import math
n, k = map(int, input().split(' '))

if n <= k**2:
    k = math.ceil(n**0.5)

l = math.ceil(n/k)
mod = n % k
grid = [('*' *k) + ('.' *(l-k)) for i in range(n//k)]
if mod:
    grid.append(('*'*mod) + ('.'*(l-mod)))

for i in range(1, len(grid)):
    grid[i] = grid[i][i:] + grid[i][:i]

print(l)
for row in grid:
    print(row)