# ASSIGNMENT MODEL
# Version 3: using n integer variables 
# with "alldiff" operator and variable subscript in objective

param n integer > 0;

set JOBS := 1..n;
set MACHINES := 1..n;

param cost {JOBS,MACHINES} > 0;

var MachineForJob {JOBS} integer >= 1, <= n;

minimize TotalCost:
   sum {j in JOBS, k in MACHINES} cost[j,MachineForJob[j]];

subj to OneJobPerMachine: 
   alldiff {j in JOBS} MachineForJob[j];