using BenchmarkTools
using StatsBase

function Day_01()
    # Robust file reading and parsing
    list_nums = Vector{Int}()
    open("files/P1.txt", "r") do file
        for line in eachline(file)
            # Split the line and parse the first two numbers
            nums = split(strip(line))
            if length(nums) >= 2
                push!(list_nums, parse(Int, nums[1]))
                push!(list_nums, parse(Int, nums[2]))
            end
        end
    end

    # Preallocate arrays and use views to avoid unnecessary allocations
    l1 = view(list_nums, 1:2:length(list_nums))
    l2 = view(list_nums, 2:2:length(list_nums))

    # Sort in-place to reduce memory allocations
    sort!(l1)
    sort!(l2)

    # Optimized part 1: Use broadcast with a temporary array to avoid repeated allocations
    p1 = sum(abs, l1 .- l2)

    # Optimized part 2: Use dictionary for efficient counting and avoid multiple passes
    freq = Dict{Int, Int}()
    for x in l2
        freq[x] = get(freq, x, 0) + 1
    end

    p2 = sum(x -> x * get(freq, x, 0), l1)

    return p1, p2
end

println(Day_01())
@btime Day_01()