Lost quite some time today in part 1

# advent-of-code

[Kroppeb]

Lost quite some time today in part 1

[Kroppeb]

How did you guys convert the output to a grid?
I noticed lists don't have a split() so I decided to convert to an actual string which took quite some time to get right.
output.toList().joinToString(separator = "") { it.toChar().toString() }.split("\n").map{it.map{it}}

[Rostyslav]

output.map { it.toChar()}.joinToString("").split("\n").map { it.toList() }

[Edgars]

I have it like this: https://github.com/edgars-supe/advent-of-code/blob/master/src/main/kotlin/lv/esupe/aoc/year2019/Day17.kt#L36-L45

[Joris PZ]

Same, just used .lines() instead of .split("\n") :

.map { it.toChar() }.toList().joinToString("").lines()

[Kroppeb]

I knew there was such a function, just forgot the name. I though it was splitLines or something

[Jakub Gwóźdź]

my Intcode works on Channel s for I/O, so I added a Flow for it and transform it like this:

@Suppress("BlockingMethodInNonBlockingContext")
private fun Flow<Char>.fullLines(): Flow<String> = flow {
    val builder = StringBuilder()
    collect {
        when (it) {
            '\n' -> emit(builder.toString()).also { builder.clear() }
            else -> builder.append(it)
        }
    }
}

this approach has some flaws (e.g. just forgets last line without any \n at the end) but is good enough for day17 🙂

[Joris PZ]

I also have a coroutine-based Intcode computer with Channels, for part 2 I turned my output Channel into a teletype by launching this:

launch {
   while (!stdout.isClosedForReceive) {
      stdout.receive().also { print(if (it < 255) it.toChar() else "Part 2: $it") }
   }
}