Quicksort in Julia using recursion

quicksort.jl

function quicksort!(a::AbstractArray, lo::Int, hi::Int)
    if lo > 0 && hi > 0 && lo < hi
        p = partition!(a, lo, hi)
        quicksort!(a, lo, p)
        quicksort!(a, p + 1, hi)
    end
end

quicksort!(a::AbstractArray) = quicksort!(a, firstindex(a), lastindex(a))

function partition!(a::AbstractArray, lo::Int, hi::Int)
    pivot = a[Int(floor((hi - lo) / 2 + lo))]
    while true
        if a[lo] < pivot lo += 1 end
        if a[hi] > pivot hi -= 1 end
        if lo >= hi return hi end
        a[lo], a[hi] = a[hi], a[lo]
    end
end

a = rand(1_000_000)
quicksort!(a)
a