题解 | #单词拆分(二)#

#
# 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
#
# 
# @param s string字符串 
# @param dic string字符串一维数组 
# @return string字符串一维数组
#
class Solution:
    # 返回该字符串的切片索引列表
    def indexstr(self, s: str, dic: List[str]) -> List[int]:
        lenth = len(s)
        res = []
        for i in range(lenth):
            if s[:i + 1] in dic:
                res.append(i)
        return res

    def recur(self, s: str, dic: List[str], tmpstr: str, lout: list ,lenth :int):
        index = self.indexstr(s, dic)
        lenth = len(s)
        curstr = tmpstr
        if s == '':
            str.strip(tmpstr)
            lout.append(tmpstr)
            return
        if index == []:
            return
        for i in index:
            if len(s) == lenth:
                tmpstr = curstr
            if tmpstr == '' :
                tmpstr = s[:i + 1]
            else :
                tmpstr = tmpstr + ' ' + s[:i + 1]
            self.recur(s[i + 1:], dic, tmpstr, lout ,lenth)

    def wordDiv(self, s: str, dic: List[str]) -> List[str]:
        # write code here
        res = []
        index = self.indexstr(s, dic)
        if index == []:
            return []
        tmpstr = ''
        lenth = len(s)
        self.recur(s, dic, tmpstr, res,lenth)
        return res