C:\test\ACA>..\junk71 -N=4
            (warning: too few iterations for a reliable count)
    Rate     b     a
b 1.45/s    --  -98%
a 85.1/s 5751%    --

C:\test\ACA>..\junk71 -N=10
            (warning: too few iterations for a reliable count)
    Rate     b     a
b 2.94/s    --  -97%
a 91.7/s 3025%    --

C:\test\ACA>..\junk71 -N=20
            (warning: too few iterations for a reliable count)
    Rate     b     a
b 4.55/s    --  -96%
a  116/s 2453%    --

C:\test\ACA>..\junk71 -N=50
            (warning: too few iterations for a reliable count)
    Rate     b     a
b 6.67/s    --  -95%
a  133/s 1900%    --

C:\test\ACA>..\junk71 -N=100
    Rate     b     a
b 7.93/s    --  -95%
a  149/s 1776%    --