advent-of-code/2021/four.nim

import std/[strutils, sequtils, options, math, parseutils, sets]
import ./common

type Board = object
  entries: seq[string]
  checked: seq[int]

let winningSets = [
  [0, 1, 2, 3, 4],
  [5, 6, 7, 8, 9],
  [10, 11, 12, 13, 14],
  [15, 16, 17, 18, 19],
  [20, 21, 22, 23, 24],
  [0, 5, 10, 15, 20],
  [1, 6, 11, 16, 21],
  [2, 7, 12, 17, 22],
  [3, 8, 13, 18, 23],
  [4, 9, 14, 19, 24]
].mapIt(it.toHashSet())

proc isBoardWinning(b: ref Board): bool =
  let s = b.checked.toHashSet()
  for w in winningSets:
    if w < s:
      return true
  return false


proc squidBingo(inputLines: seq[string]): int =
  var input: seq[string] = inputLines
  let calledNumbers: seq[string] = input[0].split ','
  input.delete 0..1

  echo calledNumbers

  # construct boards
  var boards: seq[Board]
  var board: Board = Board(entries: @[], checked: @[])
  for l in input:
    echo l
    if l.strip() == "":
      boards.add board
      echo board.entries
      board = Board(entries: @[], checked: @[])
      continue
    board.entries.add [l[0..1], l[3..4], l[6..7], l[9..10], l[12..13]].mapIt(it.strip())
    
  for n in calledNumbers:
    for b in boards:
      for i, e in b.entries:
        if n == e:
          # TODO: why can't I add here but I can add on 46?!
          b.checked.add i
      if b.isBoardWinning():
        # TODO: get unchecked entries
        # TODO: multiple their sum with last .checked
        return 9

  return 0

let input = 4.loadInput()
time("squidBingo part 1"): echo input.squidBingo()

when not defined(release):
  static:
    let testInput = """7,4,9,5,11,17,23,2,0,14,21,24,10,16,13,6,15,25,12,22,18,20,8,19,3,26,1

22 13 17 11  0
 8  2 23  4 24
21  9 14 16  7
 6 10  3 18  5
 1 12 20 15 19

 3 15  0  2 22
 9 18 13 17  5
19  8  7 25 23
20 11 10 24  4
14 21 16 12  6

14 21 17 24  4
10 16 15  9 19
18  8 23 26 20
22 11 13  6  5
 2  0 12  3  7""".split('\n')
    doAssert testInput.squidBingo() == 4512