Cacher is the code snippet organizer for pro developers

def seg(pinyin):
    """
       拼音分词,如果包括非拼音返回空
    """
    sm = ['b', 'c', 'd', 'f', 'g', 'h', 'j', 'k', 'l', 'm', 'n', 'p', 'q', 'r', 's', 't', 'w', 'x', 'y', 'z', 'sh', 'zh', 'ch']
    ymd = {'a': {'i':None, 'o':None, 'n': {'g': None}}, 
           'e': {'i':None, 'r':None, 'n': {'g': None}}, 
           'i': {'e':None, 'a':{'n':{'g':None}, 'o':None}, 'u':None, 'o':{'n':{'g':None}}, 'n':{'g':None}},
           'o': {'u':None, 'n':{'g':None}},
           'u': {'a':{'i':None, 'n':{'g':None}}, 'e':None, 'i':None, 'o':None}
          }
    result, i = '', 0
    while i < len(pinyin)-1:
        if pinyin[i] in ['s', 'z', 'c'] and pinyin[i+1] == 'h':
            result += ' ' + pinyin[i] + 'h'
            i += 2
        elif pinyin[i] in sm:
            result += ' ' + pinyin[i]
            i += 1
        else:
            result += ' '
        tmp, tmpd = '', ymd
        while i < len(pinyin):
            tmpd =tmpd.get(pinyin[i],'#')#如果字典中找不到则返回#
            if tmpd=='#':
                return None
            tmp += pinyin[i]
            i += 1            
            if not (i < len(pinyin) and tmpd and (pinyin[i] in tmpd)):#循环到底,匹配到底,不明字符
                break
        result += tmp
    return result.strip()
seg('ping')