Re: ??: [Bug-glpk] help

[Andrew Makhorin]

> Andrew,Tks.really really good.
> 
> it takes about 68.9 secs on my machine
> 
> I'm not good at maths.
> What's the reason for --mir?

Your instance is hard for the branch-and-bound method used by
default in glpsol to solve mip. Specifying '--mir' option you
enable using the branch-and-cut method, in which case glpsol tries
to generate so called mir (mixed integer rounding) inequalities
(cutting planes) at some nodes of the search tree, that allows
significantly reducing the solution time.

For more details see:
http://en.wikipedia.org/wiki/Branch_and_bound
http://en.wikipedia.org/wiki/Branch_and_cut