# Understanding the problem

• EXAMPLE 1
seqs = `[[1,2], [1,3]]`

Question: Using `seqs`, what are the shortest common supersequences we can make?
Answer: `[1,2,3]` and `[1 3 2]`.

Explanation:

• `[1,2,3]` is valid, since every sequence in `seqs` is a subsequence of `[1,2,3]`
``````[1,2,3]    [1,2,3]
* *        *   *
``````
• `[1,3,2]` is valid since every sequence in `seqs` is a subsequence of `[1,3,2]`
``````[1,3,2]    [1,3,2]
*   *      * *
``````

Solution: `False` - there are multiple such supersequences.

EXAMPLE 3
seqs = `[[1,2],[1,3],[2,3]]`

Question: Using `seqs`, what are the shortest common supersequences we can make?
Answer: `[1,2,3]`

Explanation:

• `[1,2,3]` is valid since every sequence in `seqs` is a subsequence of `[1,2,3]`
``````[1,2,3]    [1,2,3]    [1,2,3]
* *        *   *        * *
``````

Solution: `True` - solution is unique and equal to target `[1,2,3]`.

Input:
org: [4,1,5,2,6,3], seqs: [[5,2,6,3],[4,1,5,2]]

Output:
true

• what about [[1,2],[1,3],[2,3],[3,3]], [1,2,3,3], is this valid? I think it is, but return False.

``````[1]
[[1,1]]
``````

Why is this false? problem is very unclear or convoluted

Reconstruction means building a shortest common supersequence of the sequences in seqs (i.e., a shortest sequence so that all sequences in seqs are subsequences of it). Determine whether there is only one sequence that can be reconstructed from seqs and it is the org sequence.

Does this mean cycle in graph or sequence that matters - results in FALSE?

• @samuelma
Because [[1,2],[1,3],[2,3],[3,3]] can also construct [1,3,2,3], so the sequences that seqs can construct is not unique.

• @sha256pki
Although [1] is subsequence of [1,1], a single 1 can not construct [1,1]

• @Xing_ What about [6,2,1, 5,2] for [[6,2,1], [2, 1, 5, 2]] shouldn't it be a "true"? While the solution ouputs "false"

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