Edit - Code Golf Stack Exchange

You are not logged in. Your edit will be placed in a queue until it is peer reviewed.

We welcome edits that make the post easier to understand and more valuable for readers. Because community members review edits, please try to make the post substantially better than how you found it, for example, by fixing grammar or adding additional resources and hyperlinks.

Required fields*

Rev

Title*

Body*

A list \$[a_1,a_2,a_3 \cdots a_n]\$ can be uniquely represented as an unordered list of its prefixes - \$ [[a_1],[a_1, a_2], [a_1,a_2,a_3] \cdots [a_1,a_2,a_3 \cdots a_n]] \$. This can be in any order - for example, \$[1, 2, 3]\$ could be represented by any of \$[[1],[1,2],[1,2,3]]\,ドル \$[[3,2,1],[2,1],[1]]\,ドル or \$[[2, 1], [1],[3,1,2]]\$; and these are all equivalent up to order and all represent \$[1, 2, 3]\$.


Your challenge is, given a (non-empty) list of the prefixes of a list of positive integers in any order, to return the list represented by that. The list may contain repeated items. This is [tag:code-golf], shortest wins!

## Testcases

Note: the order of the output does matter, e.g. for the third test case you must output `[6, 4, 8, 7]`, not `[7, 4, 8, 6]`.

```
[[1], [1, 2], [1, 2, 3]] -> [1, 2, 3]
[[2, 1], [1], [3, 1, 2]] -> [1, 2, 3]
[[6, 4, 8], [7, 4, 8, 6], [6, 4], [6]] -> [6, 4, 8, 7]
[[6, 2, 3, 1], [1, 2], [1], [6, 1, 2], [2, 2, 3, 1, 6]] -> [1, 2, 6, 3, 2]
[[2], [30, 2, 27, 40], [27, 40, 2, 89, 30], [2, 30, 27], [27, 2]] -> [2, 27, 30, 40, 89]
[[8, 4], [4, 8, 8, 4], [4, 4, 8], [4]] -> [4, 8, 4, 8]
[[22, 98, 62, 80], [80, 98], [22, 98, 10, 62, 80, 87, 2], [98], [62, 80, 98], [22, 98, 2, 62, 80], [2, 22, 98, 62, 87, 80]] -> [98, 80, 62, 22, 2, 87, 10]
[[43, 84, 56, 19], [56, 43], [43, 56, 19], [43]] -> [43, 56, 19, 84]
```

If this is an answer to a challenge…

…Be sure to follow the challenge specification. However, please refrain from exploiting obvious loopholes. Answers abusing any of the standard loopholes are considered invalid. If you think a specification is unclear or underspecified, comment on the question instead.
…Try to optimize your score. For instance, answers to code-golf challenges should attempt to be as short as possible. You can always include a readable version of the code in addition to the competitive one. Explanations of your answer make it more interesting to read and are very much encouraged.
…Include a short header which indicates the language(s) of your code and its score, as defined by the challenge.

More generally…

…Please make sure to answer the question and provide sufficient detail.
…Avoid asking for help, clarification or responding to other answers (use comments instead).

Draft saved

Draft discarded