CPLEX debug window freezes - c++

Question

I am trying to code my math model in CPLEX language using C++ (Concert Technology). when I run my code in the compiler window read my inputs and freezes. when trying to debug my code, the visual studio shows the following line as a breakpoint.
//constraint 2
for (cc = 0; cc < NumberOfCourses; cc++) {
IloExpr Constraint2(env);
for (rr = 0; rr < AvailableRooms; rr++) {
Constraint2 += RoomCapacity[rr] * Y[cc][rr];
mod.add(Constraint2 >= Students[cc]); // this line
Constraint2.end();
}
}
i have set up the parameters and variables as follow:
double RoomCapacity[AvailableRooms];
double Students[NumberOfCourses];
//Ycr
IloBoolVarArray2 Y(env, NumberOfCourses);
for (cc = 0; cc < NumberOfCourses; cc++)
Y[cc] = IloBoolVarArray(env, AvailableRooms);
I do not understand what is wrong with my constraint!

Answer 1

Your code is wrong: In the very first inner iteration you add Constraint2 to your model and then you end() that variable. So in the second inner iteration, you are doing Constraint2 += ... while the Constraint2 object was already deleted. This will lead to undefined behavior (hang, crash, ...).
I guess what you wanted to write is this (pull add() and end() out of the inner loop):
for (cc = 0; cc < NumberOfCourses; cc++) {
IloExpr Constraint2(env);
for (rr = 0; rr < AvailableRooms; rr++) {
Constraint2 += RoomCapacity[rr] * Y[cc][rr];
}
mod.add(Constraint2 >= Students[cc]);
Constraint2.end();
}