Before the solving process STARTS, the original problem is copied. This copy is called "transformed problem", and all modifications during the pre solving and solving process are only applied to the transformed problem.

This has two main advantages: first, the user can also modify the problem after PARTIALLY solving it. All modifications done by SCIP (pre solving, cuts, and variable fixings) during the PARTIAL solving process will be deleted together with the transformed problem; the user can modify the original problem and RESTART solving. Second, the feasibility of solutions is always tested on the original problem!

Before the solving process starts, the original problem is copied. This copy is called "transformed problem", and all modifications during the pre solving and solving process are only applied to the transformed problem.

This has two main advantages: first, the user can also modify the problem after partially solving it. All modifications done by SCIP (pre solving, cuts, and variable fixings) during the partial solving process will be deleted together with the transformed problem; the user can modify the original problem and restart solving. Second, the feasibility of solutions is always tested on the original problem!