n,m= map(int, input().split())
a='.|.'
t='.|.'
x=[]
for i in range (1,n+1):
    p=0
    if i<(n+1)/2:
        print(a.center(m,'-'))
        a=a+'.|.'+'.|.'
    elif i==(n+1)/2:
        print('WELCOME'.center(m,'-'))
    
for i in range(n-2, 0, -2):
        print((t * i).center(m, "-"))