adventofcode-2023/day_04/solution_04b.nim

import std/[cmdline, strformat]

import common

var fn = if paramCount() > 0: paramStr(1) else: "input_04.txt"
var cards = parseInput(readFile(fn))
var stack = cards
var result = 0

while stack.len > 0:
    result += len(stack)
    var extra_cards: seq[Card]

    for card in stack:
        if card.value > 0:
            extra_cards.add(cards[card.idx + 1..min(card.idx + card.value, cards.len - 1)])

    stack = extra_cards

echo &"Cards processed: {cards.len}"
echo &"Result: {result}"

case fn:
    of "input_04.txt":
        assert result == 11787590
    of "sample_input_04.txt":
        assert result == 30