sarahzrf

def neighbors(grid, x, y)
  ns = []
  ns << grid[y][x - 1] if x > 0
  ns << grid[y][x + 1] if x + 1 < grid[y].length
  ns << grid[y - 1][x] if y > 0
  ns << grid[y + 1][x] if y + 1 < grid.length
  ns
end

map = $<.map {|l| l.chomp.chars.map(&:to_i)}

sarahzrf

require 'set'

def group(obs_raw)
  obs = Hash.new {Set.new("abcdefg".chars)}
  obs_raw.each do |word|
    obs[word.length] &= Set.new(word.chars)
  end
  obs
end

sarahzrf

count = 0

$<.each do |l|
  outs = l.chomp.split(' | ')[1].split
  count += outs.count {|o| [2, 4, 3, 7].include? o.length}
end

print count

sarahzrf

class Integer
  def sumtorial
    (0..self).sum
  end
end

def cost(counts, x0)
  counts.sum {|x, n| (x0 - x).abs.sumtorial * n}
end

sarahzrf

def cost(counts, x0)
  counts.sum {|x, n| (x0 - x).abs * n}
end

count_by_pos = Hash.new(0)

gets.chomp.split(',').map(&:to_i).each do |x|
  count_by_pos[x] += 1
end

sarahzrf

def cost(counts, x0)
  counts.sum {|x, n| (x0 - x).abs * n}
end


count_by_pos = Hash.new(0)

gets.chomp.split(',').map(&:to_i).each do |x|
  count_by_pos[x] += 1
end

sarahzrf

def advance(fish)
  new_fish = Hash.new(0)
  fish.each do |timer, count|
    if timer > 0
      new_fish[timer - 1] += count
    elsif timer == 0
      new_fish[6] += count
      new_fish[8] += count
    else
      raise "wtf?"

sarahzrf

def range(i, j)
  return (i..j).each if i <= j
  Enumerator.new do |y|
    loop do
      y << i
      break if i == j
      i -= 1
    end
  end
end

sarahzrf

lines = $<.map do |l|
  l =~ /(\d+),(\d+) -> (\d+),(\d+)/
  [[$1.to_i, $2.to_i], [$3.to_i, $4.to_i]]
end

map = Hash.new(0)

lines.each do |(x1, y1), (x2, y2)|
  x1, x2 = [x1, x2].sort
  y1, y2 = [y1, y2].sort

sarahzrf

lines = $<.map do |l|
  l =~ /(\d+),(\d+) -> (\d+),(\d+)/
  [[$1.to_i, $2.to_i], [$3.to_i, $4.to_i]]
end

map = Hash.new(0)

lines.each do |(x1, y1), (x2, y2)|
  if x1 == x2
    x = x1