(!******************************************************
   Mosel Example Problems
   ====================== 

   file burglari.mos
   `````````````````
   Use of index sets.
   
   (c) 2008 Fair Isaac Corporation
       author: S. Heipcke, 2001, rev. 2006
*******************************************************!)

model Burglari
 uses "mmxprs"
 
 declarations
  WTMAX = 102                    ! Maximum weight allowed
  ITEMS = {"camera", "necklace", "vase", "picture", "tv", "video", 
           "chest", "brick"}     ! Index set for items
  
  VALUE: array(ITEMS) of real    ! Value of items
  WEIGHT: array(ITEMS) of real   ! Weight of items
  
  take: array(ITEMS) of mpvar    ! 1 if we take item i; 0 otherwise
 end-declarations

 VALUE::(["camera", "necklace", "vase", "picture", "tv", "video", 
          "chest", "brick"])[15,100,90,60,40,15,10,1]
 WEIGHT::(["camera", "necklace", "vase", "picture", "tv", "video", 
           "chest", "brick"])[2,20,20,30,40,30,60,10]

! Objective: maximize total value
 MaxVal:= sum(i in ITEMS) VALUE(i)*take(i) 

! Weight restriction
 sum(i in ITEMS) WEIGHT(i)*take(i) <= WTMAX

! All variables are 0/1
 forall(i in ITEMS) take(i) is_binary  

 maximize(MaxVal)                 ! Solve the MIP-problem

! Print out the solution
 writeln("Solution:\n Objective: ", getobjval)
 forall(i in ITEMS)  writeln(" take(", i, "): ", getsol(take(i)))

! Deliberately introduced error to test redirection of error stream
 writeln(getsol(take("t")))
end-model