Compare permutaion of two numbers efficiently?

General Usage Performance
30

depending on the size of your vectors and the size of the numbers it may be worth preallocating test

this does not reflect the updates above though


function isperm3(test,a,b)
    fill!(test,0)
    while a > 0 && b > 0
        a, a_ind = divrem(a, 10)
        b, b_ind = divrem(b, 10)
        test[a_ind + 1] += 1
        test[b_ind + 1] -= 1
    end
    a != 0 || b != 0 && return false
    !any(!=(0), test)
end

function isperm3(a::Vector,b::Vector)
    sz=length(a)
    res = falses(sz)
    test = fill(0, 10)
    @inbounds for i=1:sz
        res[i] = _isperm(test,a[i],b[i]) 
    end
    return res
end

@btime isPerm2.($x,$y); # 103 micro seconds
@btime isperm3($x,$y) #70 micro seconds