30 lines
711 B
Plaintext
30 lines
711 B
Plaintext
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set EVAC;
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set DEST;
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set NODES := EVAC union DEST;
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set EDGES within {NODES,NODES};
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param population {EVAC } >= 0;
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param capacity {DEST } >= 0;
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param edgecapacity {EDGES} >= 0;
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var Flow {(a,b) in EDGES} >= 0;
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minimize TotalCost:
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+ (sum {(a,b) in EDGES} Flow[a,b])
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;
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subject to EvacMaximumCapacity {n in EVAC}:
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+ population[n] # population of city
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+ sum {(a,n) in EDGES} Flow[a,n] # flow into city
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- sum {(n,b) in EDGES} Flow[n,b] # flow out of city
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<= 0
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;
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subject to DestMaximumCapacity {n in DEST}:
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+ sum {(a,n) in EDGES} Flow[a,n] # flow into city
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- sum {(n,b) in EDGES} Flow[n,b] # flow out of city
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- capacity[n] # capacity of city to take population
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<= 0
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;
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