alph = list('abcdefghijklmnopqrstuvwxyz')
    w = ((size*2) - 1)*2 - 1
    
    print(alph[size-1].center(w, '-'))
    for i in range(1, size):
        print(("-".join(alph[size-1 : size-1-i : -1]) + '-' + "-".join(alph[size-1-i : size])).center(w, '-'))
        
    for i in range(size-2, 0, -1):
        print(("-".join(alph[size-1 : size-1-i : -1]) + '-' + "-".join(alph[size-1-i : size])).center(w, '-'))
    if size > 1:
        print(alph[size-1].center(w, '-'))