Python Challenge (level 10)

URI: http://www.pythonchallenge.com/pc/return/bull.html
Username: huge; password: file
说明:
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解题方法:

import itertools

def look_and_say (length):
    table = {
        ("1", "1", "1"): "31",
        ("1", "1"): "21",
        ("1", ): "11",
        ("2", "2", "2"): "32",
        ("2", "2"): "22",
        ("2", ): "12",
        ("3", "3", "3"): "33",
        ("3", "3"): "23",
        ("3", ): "13"
    }

    prec, result = "1", [1]

    for i in xrange(length - 1):
        prec = "".join(table[tuple(l)] for e, l in itertools.groupby(prec))
        result.append(int(prec))

    return result

print len(str(look_and_say(31)[30]))

过关答案:
5808