advent-of-code/2021/nim/day25.nim

40 lines
964 B
Nim

import ./common, std/[strutils, hashes, sugar]
proc p1(input: Lines): uint64 =
var h = input.len
var w = input[0].len
var cukes = input
while true:
var nextCukes = cukes
let startHash = cukes.hash
for y,line in cukes.pairs:
for x,c in line.pairs:
let tx = if x >= w - 1: 0 else: x + 1
if c == '>' and cukes[y][tx] == '.':
nextCukes[y][x] = '.'
nextCukes[y][tx] = '>'
cukes = nextCukes
for y,line in cukes.pairs:
for x,c in line.pairs:
let ty = if y >= h - 1: 0 else: y + 1
if c == 'v' and cukes[ty][x] == '.':
nextCukes[y][x] = '.'
nextCukes[ty][x] = 'v'
inc result
if nextCukes.hash == startHash: break
cukes = nextCukes
proc p2(input: Lines): uint64 =
0
doDayX 25, (n: int) => n.loadInput, p1, p2, ("""v...>>.vv>
.vv>>.vv..
>>.>v>...v
>>v>>.>.v.
v>v.vv.v..
>.>>..v...
.vv..>.>v.
v.v..>>v.v
....v..v.>""".split('\n'), 58'u64, 0'u64)