In this chapter we found that simply rounding off non-integer simplex solution values for models requiring integer solutions is not always appropriate. Rounding can often lead to suboptimal results. Therefore, direct solution approaches using the computer are needed to solve the three forms of linear integer programming modelstotal integer models, 01 integer models, and mixed integer models.
Having analyzed integer problems and the computer techniques for solving them, we have now covered most of the basic forms of linear programming models and solution techniques. Two exceptions are the transportation model and a problem that contains more than one objective, goal programming. These special cases of linear programming are presented in the next two chapters.