< >model:
sets:
city/1..5/:u;
link(city,city):dist,x;
endsets
data:
dist=50000 132 217 164 58
132 50000 290 201 79
217 290 50000 113 303
164 201 113 50000 196
58 79 303 196 50000;
enddata
n=@size(city);
min=@sum(link:dist*x);
@for(city(k) sum(city(i):x(i,k))=1;);
@for(city(k) sum(city(j):x(k,j))=1;);
@for(city(k) for(city(j)|j #GT# 1 #and #k#GT#1:u(j)-u(k)+n*x(j,k)<n-1;));
@for(link:@bin(x););
end</P>
< >里面的U(I)指什么东西,怎么算出来的</P> |