(!****************************************************** Mosel Example Problems ====================== file b3jobshop.mos `````````````````` Job shop production planning. (c) 2008 Fair Isaac Corporation author: S. Heipcke, Mar. 2002, rev. Nov. 2017 *******************************************************!) model "B-3 Job shop" uses "mmxprs" declarations JOBS=1..8 ! Set of jobs (operations) DUR: array(JOBS) of integer ! Durations of jobs on machines ARC: dynamic array(JOBS,JOBS) of integer ! Precedence graph DISJ: dynamic array(JOBS,JOBS) of integer ! Disjunctions between jobs start: array(JOBS) of mpvar ! Start times of jobs finish: mpvar ! Schedule completion time y: dynamic array(range) of mpvar ! Disjunction variables end-declarations initializations from 'b3jobshop.dat' DUR ARC DISJ end-initializations BIGM:= sum(j in JOBS) DUR(j) ! Some (sufficiently) large value ! Precedence constraints forall(j in JOBS) finish >= start(j)+DUR(j) forall(i,j in JOBS | exists(ARC(i,j)) ) start(i)+DUR(i) <= start(j) ! Disjunctions d:=1 forall(i,j in JOBS | i<j and exists(DISJ(i,j)) ) do create(y(d)) y(d) is_binary start(i)+DUR(i) <= start(j)+BIGM*y(d) start(j)+DUR(j) <= start(i)+BIGM*(1-y(d)) d+=1 end-do ! Bound on latest completion time finish <= BIGM ! Solve the problem: minimize latest completion time minimize(finish) ! Solution printing writeln("Total completion time: ", getobjval) forall(j in JOBS) writeln(j, ": ", getsol(start(j)), "-", getsol(start(j))+DUR(j)) end-model