递归和回溯_leetcode131

class Solution(object):
    def partition(self, s):
        """
        :type s: str
        :rtype: List[List[str]]
        """
        self.res =[]

        ans = []

        self.findDivide(s,ans)

        print self.res

        return self.res

    def findDivide(self,s,ans):

        if not s :
           #print ans
           self.res.append(ans[0:])

           # print self.res

           return


        length = len(s)
        for i  in range(1,length+1):

            firstDivide  = s[0:i]

            print firstDivide

            if self.isHuiwen(firstDivide):

                ans.append(firstDivide)
                self.findDivide(s[i:],ans)
                ans.pop()

            else:
                continue


    def isHuiwen(self,s):

        length = len(s)

        if length == 1:
            return True


        mid = (length + 1) / 2

        start = 0
        end = length-1


        while mid <= end:

            if s[start] == s[end]:
                start += 1
                end -= 1
                continue

            else:
                return False

        return True





s = Solution()

sl = "efe"

s.partition(sl)

hw = "abcba"

# print s.isHuiwen(hw)