58 lines
1.7 KiB
Nim
58 lines
1.7 KiB
Nim
import std/[strutils, sequtils, options, math, parseutils, sets, strformat, algorithm, tables]
|
|
import ./common
|
|
|
|
proc toPointPair(s: string): (int, int, int, int) =
|
|
let nums = s.split(" -> ").mapIt(it.split(',').mapIt(it.parseInt())).concat()
|
|
(nums[0], nums[1], nums[2], nums[3])
|
|
|
|
proc part1(inputLines: seq[string]): int =
|
|
var points: CountTable[(int, int)] = initCountTable[(int, int)](1000)
|
|
for l in inputLines:
|
|
let (x1, y1, x2, y2) = l.toPointPair()
|
|
if x1 == x2 or y1 == y2:
|
|
for x in min(x1, x2)..max(x1, x2):
|
|
for y in min(y1, y2)..max(y1, y2):
|
|
points.inc((x, y))
|
|
for p in points.values():
|
|
if p >= 2:
|
|
inc result
|
|
|
|
proc part2(inputLines: seq[string]): int =
|
|
var points: CountTable[(int, int)] = initCountTable[(int, int)](1000)
|
|
for l in inputLines:
|
|
let (x1, y1, x2, y2) = l.toPointPair()
|
|
let ang = arctan2(float(y2 - y1), float(x2 - x1)) * 180 / PI
|
|
if (ang.abs() mod 90) == 45.0:
|
|
var x = x1
|
|
var y = y1
|
|
let xd = if x1 > x2: -1 else: 1
|
|
let yd = if y1 > y2: -1 else: 1
|
|
while x >= min(x1, x2) and x <= max(x1, x2) and y >= min(y1, y2) and y <= max(y1, y2):
|
|
points.inc((x, y))
|
|
x += xd
|
|
y += yd
|
|
elif x1 == x2 or y1 == y2:
|
|
for x in min(x1, x2)..max(x1, x2):
|
|
for y in min(y1, y2)..max(y1, y2):
|
|
points.inc((x, y))
|
|
for p in points.values():
|
|
if p >= 2:
|
|
inc result
|
|
|
|
let input = 5.loadInput()
|
|
time("day 5 part 1"): echo input.part1()
|
|
time("day 5 part 2"): echo input.part2()
|
|
|
|
when not defined(release):
|
|
let testInput = """0,9 -> 5,9
|
|
8,0 -> 0,8
|
|
9,4 -> 3,4
|
|
2,2 -> 2,1
|
|
7,0 -> 7,4
|
|
6,4 -> 2,0
|
|
0,9 -> 2,9
|
|
3,4 -> 1,4
|
|
0,0 -> 8,8
|
|
5,5 -> 8,2""".split('\n')
|
|
doAssert testInput.part1() == 5
|
|
doAssert testInput.part2() == 12
|