The instances have varying "difficulty", but you should expect to be able to find a feasible solution for all of them within the given computer time (but probably not with the first versions of your program, and perhaps not on every run). All the instances have at least one perfect solution, that is a solution with no constraint violations, hard or soft, but you shouldn't expect to find them in the time given. Twenty such instances will be used for evaluation of the algorithms, ten are given below, and ten more will appear here two weeks before the deadline (March 17th 2003).
Here are the first ten competition problem instance files:
And here are the second ten competition problem instance files: