Day 22 Part 2.

Change-Id: I60222815834fd3180a842d3c0f1f70bc9ed2ed67
This commit is contained in:
Chris Hodges 2023-12-22 10:28:32 +01:00
parent 50a8574a10
commit 946048f3f1

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@ -152,7 +152,8 @@ fun main() {
fun parts(input: List<String>, width: Int, height: Int): Pair<Int, Int> {
val bricks = input.mapIndexed { id, it ->
val (x1, y1, z1, x2, y2, z2) = "(\\d+),(\\d+),(\\d+)~(\\d+),(\\d+),(\\d+)".toRegex().matchEntire(it)?.destructured!!
val (x1, y1, z1, x2, y2, z2) = "(\\d+),(\\d+),(\\d+)~(\\d+),(\\d+),(\\d+)".toRegex()
.matchEntire(it)?.destructured!!
Brick(id, x1.toInt(), y1.toInt(), z1.toInt(), x2.toInt(), y2.toInt(), z2.toInt())
}
.sortedBy { it.z2 }
@ -179,16 +180,23 @@ fun main() {
brickTopZ[y * width + x] = flatTopZ + b.h()
}
}
//brickTopZ.asSequence().chunked(width).joinToString("\n") { it.joinToString(" ") { String.format("%3d", it) } }.println()
//println()
}
val fallingSet = HashSet<Brick>()
//println(bricks.map { "%c: %d".format(('A' + it.id), it.onTopBricks.size) })
val disBricks = bricks.filterNot { it.onTopBricks.all { it.uponBricks.size != 1 } }
val safeBricks = bricks.size - disBricks.size
println(disBricks)
val fallingBricks = disBricks.map { it.onTopBricks.filter { it.uponBricks.size < 2 }.size }.sum()
return safeBricks to fallingBricks
var sum = 0
for (brick in disBricks) {
val fallingSet = HashSet<Brick>()
val removeQueue = ArrayDeque<Brick>()
fallingSet.add(brick)
removeQueue.add(brick)
while (removeQueue.isNotEmpty()) {
val falling = removeQueue.removeFirst()
fallingSet.add(falling)
removeQueue.addAll(falling.onTopBricks.filter { it.uponBricks.subtract(fallingSet).isEmpty() })
}
sum += fallingSet.size - 1
}
return safeBricks to sum
}
// test if implementation meets criteria from the description, like: