set AGENTS;
set TASKS;
set LINKS = AGENTS cross TASKS;
 
param cost {LINKS} >= 0;      

minimize Total_Cost;

node agent {k in AGENTS}: net_out = 1;

node task {k in TASKS}: net_in = 1;

arc X {(i,j) in LINKS} >= 0, from agent[i], to task[j], obj Total_Cost cost[i,j];