Day 6: Guard Gallivant

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FAQ

  • CameronDevOPM
    2·
    5 days ago

    How did you detect loops? I just ran for 100000 steps to see if I escaped, got my time down to 3s by doing only 10000 steps.

    • TunaCowboy@lemmy.world
      2·
      5 days ago

      I added each visited position/direction to a set, and when a ‘state’ is reached again you have entered a loop:

      v = set()
while t[g.r][g.c] != 'X':
    state = (g.r, g.c, g.d)
    if state in v:
        acc += 1
        break
    v.add(state)
    g.move(t)

      You can view my full solution here.

    • Leavingoldhabits@lemmy.world
      2·
      5 days ago

      Not who you asked but: I save coordinates and direction into a vector each time the guard faces a #. Also every time the guard faces a #, I check if the position exists in the vector, if true, it’s an infinite loop. 78ms rust aolution.

      • CameronDevOPM
        1·
        5 days ago

        That’s probably quite optimal, compared with checking every state in the path, or running off a fixed number of steps