04

🎄 Day 04

In Tokiscript

This day was pretty fun. I cant really tell why, but it was funner than the other days. Maybe im just getting more comfy writing in Tokiscript, tho it did almost shoot me in the leg this day due to the way it handles variables and scopes with lambdas.

The function ForeachDelimed declares its own variable pos, which it uses to keep track of the position in the string. It then calls the lambda (callback) that you passed into it. But Tokiscript lets you access any and all variables from the lambda. So when i declared a global variable called pos inside part 2 and tried to use it inside the lambda, things were not working as expected. The local variable pos inside ForeachDelimed was overshadowing the global variable, so when i tried to read/write pos inside the lambda, i was really reading the local variable that ForeachDelimed declared and not the one i declared globally. If Tokiscript was really a serious language i would have to fix this in some way but since its not, im not gonna do anything about it other than keep it in mind. The easy fix was to just rename the variable from pos to lineNum.

The part 2 code also originally took a really long time to run and i optimized it to be almost instant. Here is a part of the original slow code that replaced the lines 14-36:

let lines = freadstr("input.txt"):Split("\n")
let cards = array(lines:len()):Fill(1)

foreach pos, line in lines
    let sides   = line[(":" in line) + 2, nil]:Split(" | ")
    let winning = ParseNumberListString(sides[0])
    let yours   = ParseNumberListString(sides[1])
    let count   = 0

    foreach n in yours
        if n in winning /= nil
            count ++ 1
        end
    end

    for let i = 1; i <= count; i ++ 1
        if pos + i >= cards:len()
            break
        end

        cards[pos + i] ++ cards[pos]
    end
end

Quickstart

To run part 1 or part 2, do:

$ make part1
$ make part2