set ORIG;
set DEST;

param LINKS{ORIG, DEST} default 0;

for {i in ORIG, j in DEST} printf "LINKS[%s,%s] = %g \n",i,j,LINKS[i,j];

data;

set ORIG := GARY CLEV PITT;
set DEST := FRA DET LAN WIN STL FRE LAF;


param LINKS : FRA DET LAN WIN STL FRE LAF :=
     GARY   1 2 3 4 5 6 .
     CLEV   . 2 . 4 . 6 .
     PITT   1 2 3 4 5 6 7;
end;