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Carlos is hoping to strike it rich with his new consulting firm, Carlos
Structures Industries (CSI). With a solid mission statement and a can-do
attitude, he's sure to succeed in the wide world of bespoke data structures.
_ "Our vision is to synergistically leverage our core competencies to deliver
competitive market solutions that assertively meet our clients' needs." _
His first client, the well-known translation firm Treehouse, is looking to
update their logo. Treehouse wants their logo to be a rooted tree with **N**
nodes numbered 1 through **N**. They have a rough idea of what the tree should
look like, but they want Carlos to finish fleshing it out. In particular, they
have **M** requirements, the _i_th of which states that the [lowest common
ancestor](https://en.wikipedia.org/wiki/Lowest_common_ancestor) of nodes
**Xi** and **Yi** must be node **Zi**.
Carlos's goal is to find any valid tree consistent with all of these
requirements if possible, or to determine that no such tree exists.
### Input
Input begins with an integer **T**, the number of tree designs. For each
design, there is first a line containing the space-separated integers **N**
and **M**. Then **M** lines follow, the _i_th of which contains the space-
separated integers **Xi**, **Yi**, and **Zi**.
### Output
For the _i_th design, print a line containing "Case #_i_: " followed by a
description of a valid rooted tree if possible, or the string "Impossible" if
no valid tree exists. A tree description is **N** space-separated integers,
the _j_th of which is node _j_'s parent (or 0 if node _j_ is the root).
### Constraints
1 ≤ **T** ≤ 100
2 ≤ **N** ≤ 60
1 ≤ **M** ≤ 120
1 ≤ **Xi**, **Yi**, **Zi** ≤ **N**
**Xi** ≠ **Yi**
### Explanation of Sample
In the first case, the LCA of nodes 1 and 2 in the chosen tree is 3, as
required. This is the only valid output for this case.
In the third case, "2 3 0 3" would also be accepted, while no other outputs
would be.
In the fifth and sixth cases, multiple possible outputs would be accepted.
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