advent-of-code/2021
advent-of-code/2021
1
0
Fork 0
Code Activity

day(06): make it functional

Browse source 
Signed-off-by: Matej Focko <mfocko@redhat.com>
This commit is contained in:
Matej Focko 2021-12-06 10:37:13 +01:00
parent d7cde13a2e
commit 0df8adcc08
1 changed files with 10 additions and 13 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

13
src/day06/Day06.kt
View file

@ -2,20 +2,17 @@ package day06
import readInputAsCommaSeparatedInts import readInputAsCommaSeparatedInts
fun howManyAfter(input: List<Int>, days: Int): Long { fun howManyAfter(input: List<Int>, days: Int): Long =
var counts = List(9) { i -> input.count { it == i }.toLong() } (1..days)
.fold(List(9) { i -> input.count { it == i }.toLong() }) { counts, _ ->
for (day in 1..days) { List(9) { i ->
counts = List(9) { i ->
when (i) { when (i) {
6 -> counts[0] + counts[7] 6 -> counts[0] + counts[7]
else -> counts[(i + 1) % 9] else -> counts[(i + 1) % 9]
} }
} }
} }
.sum()
return counts.sum()
}
fun main() { fun main() {
val testInput = readInputAsCommaSeparatedInts(6, "test_input") val testInput = readInputAsCommaSeparatedInts(6, "test_input")