1) This type of problem is called 'Balanced Partition'.
2) Watch the video #7 on the subject at http://people.csail.mit.edu/bdean/6.046/dp/
3) Another great video on the subject: http://www.youtube.com/watch?v=EH6h7WA7sDw

A very good resource, but it still very hard for me to understand though...:(

very thanks, I understood!

thanks

thanks a lot :)

Thanks for the hints: using dynamic programming.

Thank you so much, man

Thanks a lot...
^_^