amazing and hillarious,
2 {. i
+------------------------------------------+--------------------------------------------+
|y =. y (turn)(on)(887,9)(through)(959,629)|y =. y
(turn)(on)(454,398)(through)(844,448)|
+------------------------------------------+--------------------------------------------+
i creates these boxes with 1 statement per line.
3 : i
creates a verb equivalent to if each of those boxes were a line in a multiline
definition.
'`off on toggle'
all are dyadic verbs, and turn adverb is set to just return y (no op) to serve
as the x of the dyad.
through makes a matrix the same size as y, but with all of the cells in the
rectangle set to 1.
'`off on toggle' =: >`+.`~:
is a simple cell comparison of current value to 1.
----- Original Message -----
From: Henry Rich <[email protected]>
To: [email protected]
Sent: Sunday, December 6, 2015 6:37 PM
Subject: Re: [Jprogramming] adventofcode 6
Part 1:
i =. <@('y =. y ' , ;@(<@('(' , ,&')');._2)@:(,&' '));._2 wd 'clippaste'
through =: (1000 1000 {. ({. ($&1)))/@(-~/\)@:-@(,:~ >:)
turn =: 1 : 'u'
'`off on toggle' =: >`+.`~:
+/@, 3 : i 1000 1000 $ 0
For part 2, use
'`off on toggle' =: (0 >. -)`+`(+ +:)
On 12/6/2015 6:03 PM, David Lambert wrote:
> Ryan made a mask shape 1000 1000 and applied it appropriately to a
> cumulative array. Pascal updated the accumulation array in place. I
> did so likewise but used the dyadic form of amend with gerund m.
> Pascal computed the index in one place, which I prefer to my 3 sites.
>
> g
> [: r/ [: _&". {::"0 1
>
> r NB. absolute value not required
> ([ + i.@:|@:(-/)) >:
>
>
> NB. noun L is the array of lights.
>
> identify NB. whoops! returns a vector
> 0 1 2 #~ 'turn on'&({.@E.) , 'turn off'&({.@E.) , 'toggle'&({.@E.)
>
> on
> 3 : 0
> I=:([: < 2 6&g ; 4 8&g)@;:y
> NB. L=:I (1:)`([)`(])}L
> L=:I (>:@:{)`([)`(])}L
> EMPTY
> )
>
> off
> 3 : 0
> I=:([: < 2 6&g ; 4 8&g)@;:y
> NB.I (0:)`([)`(])}L
> L=:I ((0>.<:)@:{)`([)`(])}L
> EMPTY
> )
>
> toggle
> 3 : 0
> I=:([: < (<:2 6)&g ; (<:4 8)&g)@;:y
> NB. L=: I (-.@:{)`([)`(])}L
> L=:I (2+{)`([)`(])}L
> EMPTY
> )
>
>
> NB. what the heck??? Why is this zero?
>
> +/, L [ on`off`toggle@.({.@identify)@,;._2(1!:1)<'/tmp/a' [ L=:1000
> 1000$0
> 0
> +/,L
> 14110788
>
>
>
>
>> Date: Mon, 07 Dec 2015 08:46:59 +1100
>> From: "Ryan Eckbo"<[email protected]>
>> To: programming<[email protected]>
>> Subject: Re: [Jprogramming] adventofcode 6
>> Message-ID:<[email protected]>
>> Content-Type: text/plain; format=flowed
>>
>> How do your on/off/toggle functions work? My solution also updates a
>> global matrix,
>> but my implementation doesn't feel good. Looking forward to seeing
>> nicer solutions.
>>
>> xind=: 3 : 0&{ + [: i. >:@:(-/)@:(2 0&{)
>> yind=: 3 : 1&{ + [: i. >:@:(-/)@:(3 1&{)
>> mkmask=: 3 : '1 inds} 1000 1000 $ 0 [ inds=: < (xind y);(yind y)'
>> on=: 3 : 'lights=: lights + mkmask y'
>> off=: 3 : 'lights=: 0 >. lights - mkmask y'
>> toggle=: 3 : 'lights=: lights + +: mkmask y'
>> instructions=: <;._2 (' through ';',';'turn ';'') stringreplace
>> fread'/tmp/input.txt'
>>
>> lights=: 1000 1000$0
>> do each instructions
>> +/, lights
>>
>
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