# Day Eleven: Seating System import os, strutils, sequtils, sugar let input: string = paramStr(1) var terminal: seq[seq[char]] = input.readFile().strip().split('\n').map(row => @row) let height: int = terminal.len let width: int = terminal[0].len while true: var prev, future: seq[char] = @('.'.repeat(width)) # dummy floor var buffer: seq[seq[char]] = terminal for i, row in buffer: if height - i == 1: future = @('.'.repeat(width)) else: future = buffer[i+1] for j, seat in row: let threshold: int = if j == 0: count(prev[j..j+1], '#') + count($row[j+1], "#") + count(future[j..j+1], '#') elif j == width - 1: count(prev[j-1..j], '#') + count($row[j-1], "#") + count(future[j-1..j], '#') else: count(prev[j-1..j+1], '#') + count($row[j-1], "#") + count($row[j+1], "#") + count(future[j-1..j+1], '#') if seat == '#' and threshold >= 4: buffer[i][j] = 'L' elif seat == 'L' and threshold == 0: buffer[i][j] = '#' prev = row if terminal == buffer: break terminal = buffer echo count($terminal, '#') terminal = input.readFile().strip().split('\n').map(row => @row) while true: var prev, future: seq[char] = @('.'.repeat(width)) # dummy floor var buffer: seq[seq[char]] = terminal for i, row in buffer: if height - i == 1: future = @('.'.repeat(width)) else: future = buffer[i+1] for j, seat in row: var threshold: int = 0 # left for k in countdown(j-1, 0): if terminal[i][k] == '#': inc(threshold) if terminal[i][k] != '.': break # right for k in j+1 .. width - 1: if terminal[i][k] == '#': inc(threshold) if terminal[i][k] != '.': break # up for k in countdown(i-1, 0): if terminal[k][j] == '#': inc(threshold) if terminal[k][j] != '.': break # down for k in i+1 .. height - 1: if terminal[k][j] == '#': inc(threshold) if terminal[k][j] != '.': break # down-left for k in 1 .. min(i, j): if terminal[i-k][j-k] == '#': inc(threshold) if terminal[i-k][j-k] != '.': break # up-left for k in 1 .. min(height-1-i, j): if terminal[i+k][j-k] == '#': inc(threshold) if terminal[i+k][j-k] != '.': break # down-right for k in 1 .. min(i, width-1-j): if terminal[i-k][j+k] == '#': inc(threshold) if terminal[i-k][j+k] != '.': break # up-right for k in 1 .. min(height-1-i, width-1-j): if terminal[i+k][j+k] == '#': inc(threshold) if terminal[i+k][j+k] != '.': break if seat == '#' and threshold >= 5: buffer[i][j] = 'L' elif seat == 'L' and threshold == 0: buffer[i][j] = '#' prev = row if terminal == buffer: break terminal = buffer echo count($terminal, '#')