# t_zbase_n_demo4all.py

# t_zbase_n_demo4all.py

def zbase(n, b=3,length=3):
    t = b**(length)
    if n < t:
        n=n+t
        if n == 0:
            return [0]
        values = []
        for z in 'Z'*length:
            r = n % b
            n /= b
            values.append(r)
        return values[::-1]
0

ttt = 'abcdefghijklmnopqrstuvwxyz'[:4]

def base2index(base, target, length):
    result = 0
    baseLen = len(base)
    for i, value in enumerate(target):
        result += base.index(value) * baseLen**(length - 1 - i)
    return result

def index2base(base, target, length):
    result = zbase(target, len(base), length)
    if result:
        return ''.join([base[i] for i in result])

i = 0
while 1:
    t = index2base(ttt, i, 4)
    if not t:
        break
    print 'from '+str(i).zfill(3), 'to', [t], 'converted back to', base2index(ttt, t, 4)
    print
    i += 1
0