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Set i(*) supply /
'seattle', 
'san-diego' /;

Set j(*) markets /
'new-york', 
'chicago', 
'topeka' /;

Parameter d(i,j) distance in thousands of miles /
'seattle'.'new-york' Test, 
'seattle'.'chicago' NA, 
'seattle'.'topeka' +Inf, 
'san-diego'.'new-york' -Inf, 
'san-diego'.'chicago' Undf, 
'san-diego'.'topeka' 0 /;

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