题目描述

输入一个字符串,按字典序打印出该字符串中字符的所有排列。例如输入字符串abc,则按字典序打印出由字符a,b,c所能排列出来的所有字符串abc,acb,bac,bca,cab和cba。

输入描述:

输入一个字符串,长度不超过9(可能有字符重复),字符只包括大小写字母。

解答

递归

# coding:utf-8
class Solution:
    def Permutation(self, ss):
        # write code here
        if len(ss) == 0:
            return []
        if len(ss) == 1:
            return [ss]
        l1 = []
        for i in range(len(ss)):
            head = ss[i]
            for j in self.Permutation(ss[0:i] + ss[i+1:]):
                probe = head + j
                if probe not in l1:
                    l1.append(probe)
        return l1


p = Solution()
ret = p.Permutation('abc')
print ret

结束！