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Day 9. Removed all smart code.

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This commit is contained in:
Chris Hodges 2025-12-09 08:36:22 +01:00
parent 9a2a22805b
commit d2044f2d6a
1 changed files with 3 additions and 44 deletions
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47
src/aoc2025/Day09.kt
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@ -3,7 +3,6 @@ package aoc2025
import println
import readInput
import splitInts
import java.util.*
import kotlin.math.abs
/*
@ -13,7 +12,6 @@ https://adventofcode.com/2025/day/9
fun main() {
val inlineTestInput = """
7,3
7,1
11,1
11,7
@ -21,6 +19,7 @@ fun main() {
9,5
2,5
2,3
7,3
"""
fun part1(input: List<String>): Long {
@ -34,18 +33,6 @@ fun main() {
return maxArea
}
fun findRanges(set: TreeMap<Int, ArrayList<IntRange>>, x1: Int, y1: Int, x2: Int, y2: Int): Boolean {
var it = set.ceilingEntry(y1)
while (it != null && it.key <= y2) {
val xRanges = it.value.filter { it.first() >= x1 && it.last() <= x2 }
if (it.key != y1 && it.key != y2 && xRanges.size > 0) return false
if ((it.key == y1 || it.key == y2) && xRanges.size > 1) return false
// Java TreeMap is crap -- I would like to iterate from first entry to last
it = set.ceilingEntry(it.key + 1)
}
return true
}
fun intersects(coords: List<List<Int>>, x1: Int, y1: Int, x2: Int, y2: Int): Boolean {
for (z1 in 0 until coords.size) {
val z2 = if (z1 != coords.size - 1) z1 + 1 else 0
@ -72,44 +59,16 @@ fun main() {
fun part2(input: List<String>): Long {
val coords = input.map { it.splitInts(",") }
val xSpans = TreeMap<Int, ArrayList<IntRange>>()
val ySpans = TreeMap<Int, ArrayList<IntRange>>()
for (i1 in 0 until coords.size) {
val i2 = if (i1 != coords.size - 1) i1 + 1 else 0
if (i1 and 1 == 1) {
xSpans.getOrPut(coords[i1][1]) { ArrayList<IntRange>() }.add(
IntRange(
coords[i1][0].coerceAtMost(coords[i2][0]),
coords[i1][0].coerceAtLeast(coords[i2][0])
)
)
} else {
ySpans.getOrPut(coords[i1][0]) { ArrayList<IntRange>() }.add(
IntRange(
coords[i1][1].coerceAtMost(coords[i2][1]),
coords[i1][1].coerceAtLeast(coords[i2][1])
)
)
}
}
//xSpans.values.forEach { it.sortBy { it.first } }
//ySpans.values.forEach { it.sortBy { it.first } }
var maxArea = 0L
for (i1 in 0 until coords.size step 1) {
for (i2 in i1 + 1 until coords.size step 1) {
for (i1 in 0 until coords.size step 2) {
for (i2 in i1 + 2 until coords.size step 2) {
val x1 = coords[i1][0].coerceAtMost(coords[i2][0])
val x2 = coords[i1][0].coerceAtLeast(coords[i2][0])
val y1 = coords[i1][1].coerceAtMost(coords[i2][1])
val y2 = coords[i1][1].coerceAtLeast(coords[i2][1])
if (x1 == x2 || y1 == y2) continue
val area = ((x2 - x1 + 1).toLong() * (y2 - y1 + 1).toLong())
if (area > maxArea) {
// if (!findRanges(xSpans, x1, y1, x2, y2) ||
// !findRanges(ySpans, y1, x1, y2, x2)
// ) continue
if (!intersects(coords, x1, y1, x2, y2))
maxArea = area
}