iRules Solution to Day 1 of the 2022 Advent of Code. Requires iFiles as named with the test and puzzle data (with final newline)

2022_AoC_Day1.irul

ltm rule aoc_day1 {

proc find_sum { snack_list } {
    set calorie_sum 0
    foreach snack [string map { \{ "" \} "" } $snack_list] {
        set calorie_sum [expr {$calorie_sum + $snack}]
    }
    return $calorie_sum
}

proc find_max { elf_list } {
    set max 0
    foreach elf $elf_list {
        if { $elf > $max } {
            set max $elf
        }
    }
    return $max
}

when HTTP_REQUEST priority 500 {
    # Get and store test or puzzle data
    if { [HTTP::uri] eq "/test" } {
        set aoc_data [ifile get testdata]
    } elseif { [HTTP::uri] eq "/puzzle" } {
        set aoc_data [ifile get puzzledata]
    } else {
        HTTP::respond 406 content "Not an acceptable destination. You Lose, Good day, sir!"
        return
    }
    # get data ready to iterate on
    set aoc_data [split $aoc_data "\n"]
    set aoc_data [split $aoc_data "{}"]
    # iterate on the snack data
    foreach snack $aoc_data {
        if { $snack != {} } {
            # append snacks list for current elf
            lappend snacks $snack
        } elseif { [info exists snacks] } {
            # hit {}, tally up calories in last elf's snacks and append total to elf list
            set elf_calories [call find_sum $snacks]
            lappend elves $elf_calories
            # unset snacks so new elf doesn't have last elf's data
            unset -- snacks
        }
    }

    # Solving Part 1
    # find the elf with the most calories
    set elf_max [call find_max $elves]

    # Solving Part 2
    # find the three elves with the most calories and summarize
    set top_three [lrange [lsort -integer -decreasing $elves] 0 2]
    set top_three [call find_sum $top_three]

    # return the data
    HTTP::respond 200 content "\n2022 Advent of Code - Day 1\n\n\tPart one: $elf_max\n\tPart two: $top_three\n\n"
}

}