AdventOfCode-2022/day11.cr
2022-12-12 11:38:59 -08:00

59 lines
1.4 KiB
Crystal

require "advent"
require "big"
class Monkey
property items : Array(Int64)
property op : String
property divBy : Int64
property ifTrue : Int64
property ifFalse : Int64
def initialize(@items, @op, @divBy, @ifTrue, @ifFalse)
end
end
INSTS = {
"*" => ->(x: Int64, y: Int64) { x * y },
"+" => ->(x: Int64, y: Int64) { x + y }
}
def execute(inst, old, mod)
inst = inst.gsub("old", old.to_s);
l, op, r = inst.split(" ")
l = l.to_i64 % mod
r = r.to_i64 % mod
INSTS[op].call(l,r)
end
monkeys = [] of Monkey
input(2022, 11).split("\n\n").each do |it|
it = it.lines
items = it[1].split(": ")[1].split(", ").map(&.to_i64).reverse
op = it[2].split("Operation: new = ")[1]
divBy = it[3].split("Test: divisible by ")[1].to_i64
ifTrue = it[4].split(" If true: throw to monkey ")[1].to_i64
ifFalse = it[5].split(" If false: throw to monkey ")[1].to_i64
monkeys << Monkey.new(items, op, divBy, ifTrue, ifFalse)
end
counts = [0] * monkeys.size
modulus = monkeys.map(&.divBy).product
10000.times do
monkeys.each_with_index do |m, i|
while !m.items.empty?
counts[i] += 1
item = m.items.pop
item = execute(m.op, item, modulus)
item = item % modulus
if item % m.divBy == 0
monkeys[m.ifTrue].items.insert(0, item)
else
monkeys[m.ifFalse].items.insert(0, item)
end
end
end
end
counts.sort!
puts counts[-1].to_big_i * counts[-2].to_big_i