CPLEX：使用dvar的赋值对数组进行索引。

Question

我想用分配给dvar的值来引用一个数组，但CPLEX却给出了一个错误信息--"CP不能提取表达式"。但是，CPLEX却给出了一个错误信息--"CP无法提取表达式"。我该怎么做才能克服这个错误？

下面是我的问题的代码--一个基于员工可用时间的工作分配。

using CP;

{string} Employee = ...;

{string} Jobs = ...;

range EmpIDs = 0..card(Employee)-1;

{int} AvailSlot[EmpIDs] = ...;

range Slots = 1...10

dvar int Time[Jobs] in Slots;

dvar int Emp[Jobs] in EmpIDs;

subject to{

forall (x in Jobs) {
   Time[x] in AvailSlot[Emp[x]];}  //this constraints the assigned time slot for the job x to be one of the available time slots of the employee that is assigned with the same job x. 

}

先谢谢你。

Answer 1

使用CP.P.A.C.A.C.A.C.C.A.C.A.C.A.C.A.C.A.C.A.C.A.C.A.C.A.C.A.A.C.A.A.A.A.A.A.A.A.A.A.A.A.A.A.A.A.A;

{string} Employee = {"A","B"};

{string} Jobs = {"K","L"};

range EmpIDs = 0..card(Employee)-1;

{int} AvailSlot[EmpIDs] = [{1,2},{2,3}];


range Slots = 1..10;


dvar int Time[Jobs] in Slots;

dvar int Emp[Jobs] in EmpIDs;

subject to{


forall (x in Jobs) {
   //Time[x] in AvailSlot[Emp[x]];  
   or (j in EmpIDs) (j==Emp[x] && Time[x] in AvailSlot[j]);
}
}

assert forall (x in Jobs) 
   Time[x] in AvailSlot[Emp[x]];

可以正常工作