Morris' Blog 我在摸索我存在的意義、生命的意義、內涵及價值。 沒有真正神手般的厲害，套用模式是大部分的情況。 沒那麼厲害的我存在的意義為何，襯托出神的存在？ 有時候不能怪別人不給我機會，我已經開始省思， 為什麼我沒有給別人機會的原因，而是全要靠別人。 有時候我認為我與眾不同，那是因為我做不到很多人能辦到的事情。 我聽不到、玩不起來、說得不夠明瞭、理解得不夠多， 我缺少的語文能力，就是一切一切無能的判定。 為此，我不曉得能做些對別人有幫助的事情。 我知道我自己是個不服輸的性格，但現在我不得不認輸。 我沒有能力，因此我必須認輸。 我到底來這世界作什麼？處處充滿不確定性， 而我總是無法出類拔萃，想當個一般人似乎也回不了頭了。 越強大的挑戰需要越強力的支持，而我的支持是什麼？ 最近嘗試與人談話，但都是失敗的結局，沒人能接受， 不需要言語，不需要溝通，一切所想都表達不出來。

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Problem I

Knuth’s Permutation

Input: standard input

Output: standard output

There are some permutation generation techniques in Knuth’s book “The Art of Computer Programming - Volume 1”. One of the processes is as follows:

           For each permutation A1, A2, …, An-1 form n others by inserting a character n in all possible places obtaining

           n A1 A2 … An-1,         A1 n A2 … An-1,        ….,          A1 A2 …n An-1,       A1 A2, … An-1 n

           For example, from the permutation 231 inserting 4 in all possible places we get 4231 2431 2341 2314

Following this rule you have to generate all the permutation for a given set of characters. All the given characters will be different and there number will be less than 10 and they all will be alpha numerals. This process is recursive and you will have to start recursive call with the first character and keep inserting the other characters in order. The sample input and output will make this clear. Your output should exactly mach the sample output for the sample input.

Input

The input contains several lines of input. Each line will be a sequence of characters. There will be less than ten alphanumerals in each line. The input will be terminated by End of File.

Output

 For each line of input generate the permutation of those characters. The input ordering is very important for the output. That is the permutation sequence for abc and bca will not be the same. Seperate each set of permutation output with a blank line.

Sample Input:

Sample Output: