Hi susan_in_california, What is the compile line for your project? > I am having a little trouble understanding this line. It indicates that the copy-constructor for your vector<vector<int>> is consuming 14.33% of the run time. That's a lot. Especially if you've taken care not to copy your vector-of-vectors-of-ints. It appears that you missed a case. Sincerely, --Eljay
