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Diary

  • First day as a TA at Coding Dojo
  • Worked up through the automated testing portion of the Django official tutorial
  • Didn't have time to do any algorithms -- learned about a path-finding problem (2D array represents connections between nodes -- determine whether there is a path from A to B for arbitrary A and B)
    • e.g. for nodes A, B, and C
      • [ [0, 1, 0] , [0 , 0, 1], [0, 0, 0] ]
      • First entry says A is connected to B, second that B is connected to C -- so there's a path from A to C.
      • The connection relationship is not robust.  A can be connected to B without B being connected to A.  It must however in some sense give rise to another relationship that is at least transitive.  If A and B are connected, and B and C are connected, then I can get from A to C.  This does not mean, however, that I can get back from C to A.
      • Initial thought was do something with recursion.  Too complicated.  And what if you have loops?  Now it seems you just need a way to translate this information into a more manageable data structure -- for example the dynamic connectivity data structure.

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