In milps you can have an objective function to minimize/maximize and continuous variables. The techniques used are based on the characteristics of the mathemati

In milps you can have an objective function to minimize/maximize and continuous variables. The techniques used are based on the characteristics of the mathematical space of the possible solution and methods to reduce the size of space that you have to look into. The solution of milp solver are provably optimal. CP allows for constrains that are difficult to model and/or solve in milps (or even mip). There is some overlap between the two. For example, presolving in milp is basically a generalization of constraint programming.