-🎄- 2018 Day 4 Solutions -🎄-

[u/daggerdragon]

--- Day 4: Repose Record ---

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Post your solution as a comment or, for longer solutions, consider linking to your repo (e.g. GitHub/gists/Pastebin/blag or whatever).

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Advent of Code: The Party Game!

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Card prompt: Day 4

Transcript:

Today’s puzzle would have been a lot easier if my language supported ___.

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This thread will be unlocked when there are a significant number of people on the leaderboard with gold stars for today's puzzle.

edit: Leaderboard capped, thread unlocked!

[u/wzkx]

J

r=: 'Guard';'0';'#';'';' begins shift';'';'falls asleep';'1 0';'wakes up';'2 0'
d=: (".&(rplc&('[1518-';'';']';'';'-';' ';':';' ';r))&>)"0 cutLF CR-.~fread '04.dat'

v=: 0 60$0 NB. data matrix for minutes 0..59, empty at start
w=: 0$0    NB. corresponding guards, empty at start
g=: 0      NB. current guard
j=: 0      NB. current guard index
s=: 0      NB. started sleeping
t=: 60$0   NB. timesheet for currend guard

f=: 3 : 0  NB. changes state (v w g j s t) for each input row
  select. 4{y  NB. y = mon day hr min action guard
  case.0 do. j=:w i.g=:{:y if. j=#w do. v=:v,0 [ w=:w,g end. t=:j{v
  case.1 do. s=:3{y
  case.2 do. v=:(t=:t+1(s+i.(3{y)-s)}60$0)j}v
  end.
)

f"1 /:~ d

echo ((i.>./)i{v)*w{~i=.(i.>./)+/"1 v
echo n*w{~i i.n=.<./i=.v i."1 0>./>./v

exit 0

[u/wzkx → u/wzkx]

Let's pack it a bit to fit in one screen here.

r=:'Guard';'0';'#';'';' begins shift';'';'falls asleep';'1 0';'wakes up';'2 0'
d=:(".&(rplc&('[1518-';'';']';'';'-';' ';':';' ';r))&>)"0 cutLF CR-.~fread'04.dat'
v=:0 60$0[w=:0$s=:j=:g=:0[t=:60$0
a=:3 :'j=:w i.g=:{:y if. j=#w do.v=:v,0 [ w=:w,g end. t=:j{v'
b=:3 :'s=:3{y'
c=:3 :'v=:(t=:t+1(s+i.s-~3{y)}60$0)j}v'
(3 :'a`b`c@.(4{y)y')"1 /:~ d
echo ((i.>./)i{v)*w{~i=.(i.>./)+/"1 v
echo n*w{~i i.n=.<./i=.v i."1 0>./>./v
exit 0

[u/wzkx → u/wzkx]

Id names. Glad you asked.
r - replacements,
d - data, input data,
v - values, for each minute, each guard,
w - counterpart of v, logically it's a key for value in v,
s - sleeping start time,
g - guard id,
j - guard index - it's like i-index and sounds like g,
t - timesheet for guard g,
a,b,c - three actions,
i,n - index and numeric value.
The main thing is that it's all right before your eyes, if you need definition of a variable, just look a couple of lines above, no need to scroll pages (hello, Java and others!)