Day 6: Guard Gallivant

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[-] CameronDev@programming.dev 2 points 2 weeks 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.

[-] Leavingoldhabits@lemmy.world 2 points 2 weeks 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.

[-] CameronDev@programming.dev 1 points 2 weeks ago

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

[-] TunaCowboy@lemmy.world 2 points 2 weeks ago* (last edited 2 weeks 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.

this post was submitted on 06 Dec 2024

26 points (96.4% liked)

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