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exercism fetch go pov

Pov

Reparent a graph on a selected node.

Tree Reparenting

This exercise is all about re-orientating a graph to see things from a different point of view. For example family trees are usually presented from the ancestor's perspective:

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2
3
4
5
    +------0------+
    |      |      |
  +-1-+  +-2-+  +-3-+
  |   |  |   |  |   |
  4   5  6   7  8   9

But the same information can be presented from the perspective of any other node in the graph, by pulling it up to the root and dragging its relationships along with it. So the same graph from 6's perspective would look like:

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2
3
4
5
6
7
8
9
        6
        |
  +-----2-----+
  |           |
  7     +-----0-----+
        |           |
      +-1-+       +-3-+
      |   |       |   |
      4   5       8   9

This lets us more simply describe the paths between two nodes. So for example the path from 6-9 (which in the first graph goes up to the root and then down to a different leaf node) can be seen to follow the path 6-2-0-3-9

This exercise involves taking an input graph and re-orientating it from the point of view of one of the nodes.

Running the tests

To run the tests run the command go test from within the exercise directory.

If the test suite contains benchmarks, you can run these with the -bench flag:

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go test -bench .

Keep in mind that each reviewer will run benchmarks on a different machine, with different specs, so the results from these benchmark tests may vary.

Further information

For more detailed information about the Go track, including how to get help if you're having trouble, please visit the exercism.io Go language page.

Source

Adaptation of exercise from 4clojure https://www.4clojure.com/

Submitting Incomplete Solutions

It's possible to submit an incomplete solution so you can see how others have completed the exercise.