if __name__ == '__main__':
    N, M = input().split()
    N, M = int(N), int(M)
    for x in range(N - 1):
        if x % 2 == 0:
            print((".|." * (x + 1)).center(M, '-'))
    print("WELCOME".center(M, '-'))
    for x in reversed(range(N - 1)):
        if x % 2 == 0:
            print((".|." * (x + 1)).center(M, '-'))