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

   file f2crew.mos
   ```````````````
   Composing military flight crews
   
   (c) 2008 Fair Isaac Corporation
       author: S. Heipcke, Mar. 2002
*******************************************************!)

model "F-2 Flight crews"
 uses "mmxprs"

 forward procedure print_sol

 declarations
  PILOTS = 1..8                      ! Set of pilots
  ARCS: range                        ! Set of arcs representing crews
  RL, RT: set of string              ! Sets of languages and plane types

  LANG: array(RL,PILOTS) of integer  ! Language skills of pilots
  PTYPE: array(RT,PILOTS) of integer ! Flying skills of pilots
  CREW: array(ARCS,1..2) of integer  ! Possible crews
 end-declarations

 initializations from 'f2crew.dat'
  LANG PTYPE
 end-initializations

! Calculate the possible crews
 ct:=1
 forall(p,q in PILOTS| p<q and in>=10 and LANG(l,q)>=10)) and
                      (or(t in RT) (PTYPE(t,p)>=10 and PTYPE(t,q)>=10)) ) do
  CREW(ct,1):=p
  CREW(ct,2):=q
  ct+=1
 end-do

 finalize(ARCS)
 
 declarations
  fly: array(ARCS) of mpvar           ! 1 if crew is flying, 0 otherwise
 end-declarations 
 
! First objective: number of pilots flying
 NFlying:= sum(a in ARCS) fly(a)

! Every pilot is member of at most a single crew
 forall(r in PILOTS) sum(a in ARCS | CREW(a,1)=r or CREW(a,2)=r) fly(a) <= 1

 forall(a in ARCS) fly(a) is_binary
 
! Solve the problem
 maximize(NFlying)
 
! Solution printing
 writeln("Number of crews: ", getobjval)
 print_sol

! **** Extend the problem ****
 declarations
  SCORE: array(ARCS) of integer       ! Maximum scores of crews  
 end-declarations 

 forall(a in ARCS)
  SCORE(a):= max(t in RT | PTYPE(t,CREW(a,1))>=10 and PTYPE(t,CREW(a,2))>=10) 
               (PTYPE(t,CREW(a,1)) + PTYPE(t,CREW(a,2)))

! Second objective: sum of scores
 TotalScore:= sum(a in ARCS) SCORE(a)*fly(a)

! Solve the problem
 maximize(TotalScore)

 writeln("Maximum total score: ", getobjval)
 print_sol
 
!-----------------------------------------------------------------

! Solution printing
 procedure print_sol
  forall(a in ARCS)
   if(getsol(fly(a))>0) then
    writeln(CREW(a,1),  " - ", CREW(a,2))
   end-if
 end-procedure  
  
end-model