Hello everyone :)

I have a little problem:

I want to implement the following constraints (upload).

My try:

dvar boolean x[V][T];

**constraints:**

forall(t in T){sum(v in V)x[v][t]==1};

forall(v in V){sum(t in T)x[v][t]==d[v]};

But it didn´t work. ERROR:

aggregation operator forall for {boolean} not available

I hope someone could help me :)