/*
--- Part Two ---

It's getting pretty expensive to fly these days - not because of ticket prices, but because of the
ridiculous number of bags you need to buy!

Consider again your shiny gold bag and the rules from the above example:

- faded blue bags contain 0 other bags.
- dotted black bags contain 0 other bags.
- vibrant plum bags contain 11 other bags: 5 faded blue bags and 6 dotted black bags.
- dark olive bags contain 7 other bags: 3 faded blue bags and 4 dotted black bags.

So, a single shiny gold bag must contain 1 dark olive bag (and the 7 bags within it) plus 2 vibrant
plum bags (and the 11 bags within each of those): 1 + 1*7 + 2 + 2*11 = 32 bags!

Of course, the actual rules have a small chance of going several levels deeper than this example; be
sure to count all of the bags, even if the nesting becomes topologically impractical!

Here's another example:

shiny gold bags contain 2 dark red bags.
dark red bags contain 2 dark orange bags.
dark orange bags contain 2 dark yellow bags.
dark yellow bags contain 2 dark green bags.
dark green bags contain 2 dark blue bags.
dark blue bags contain 2 dark violet bags.
dark violet bags contain no other bags.

In this example, a single shiny gold bag must contain 126 other bags.

How many individual bags are required inside your single shiny gold bag?
*/

package com.curtislb.adventofcode.year2020.day07.part2

import com.curtislb.adventofcode.year2020.day07.baggage.BagCount
import com.curtislb.adventofcode.year2020.day07.baggage.BagRules
import java.nio.file.Path
import java.nio.file.Paths

/**
 * Returns the solution to the puzzle for 2020, day 7, part 2.
 *
 * @param inputPath The path to the input file for this puzzle.
 */
fun solve(inputPath: Path = Paths.get("..", "input", "input.txt")): Int {
    val file = inputPath.toFile()
    val rules = BagRules(file.readText())
    return rules.countTotalBags(BagCount("shiny gold", 1)) - 1
}

fun main() {
    println(solve())
}
