some OT: how to solve this kind of problem in our program?

[bearophileHUGS at lycos.com]

Paul McGuire:
> This little framework takes about 4.5 seconds, but with
> psyco, cuts down to about 1.3 seconds.
>
> st = time.time()
> result = []
> for p in permutations(range(1,10)):
>     aresult = func(p)
>     if aresult is not None and aresult not in result:
>         result.append(aresult)
>
> et=time.time()
> print 'time elapsed: %.4f s' % (et-st)
> for [[a0, a1, a2], [b0, b1, b2], [c0, c1, c2]] in result:
>   print '  %0d     %0d     %0d     %0d' % (a0, b0, c0, d0)
>   print '--- + --- + --- = ---'
>   print ' %0d%0d    %0d%0d    %0d%0d     %0d' %(a1, a2, b1, b2, c1,c2, d1)
>   print

If you want to more speed, put long loops always inside functions, not
inside the main body:

def main():
    st = clock()
    result = []
    for p in permutations(range(1, 10)):
        aresult = func(p)
        if aresult is not None and aresult not in result:
            result.append(aresult)

    et = clock()
    print 'time elapsed: %.4f s' % (et-st)
    for [[a0, a1, a2], [b0, b1, b2], [c0, c1, c2]] in result:
      print '  %0d     %0d     %0d     %0d' % (a0, b0, c0, d0)
      print '--- + --- + --- = ---'
      print ' %0d%0d    %0d%0d    %0d%0d     %0d' %(a1, a2, b1, b2,
c1,c2, d1)
      print

main()

If you have a bit of time you can test the speed of this code on your
computer.

Bye,
bearophile