Оптимизация СМО

function flowDir(nM)
    qN = size(nM, 1)
    nfl = count(x -> x > 0, nM)
    nl = zeros(Int, 2 * nfl)
    c = 1
    
    for a in 1:qN
        for b in 1:qN
            if nM[a, b] > 0
                nl[2*c - 1] = a
                nl[2*c] = b
                c += 1
            end
        end
    end
    
    return reshape(nl, 2, nfl)
end