lingo小菜鸡好难呀,一直报错

model:
!3发点4销售点运输问题模型;
sets:
warehouse/wh1..wh3/: capacity:
vendors/1..4/: demand:
links(warehouse,vendors): cost, volume;
endsets
!目标函数;
min=@sum(links: cost*volume);
!需求约束;
@for(vendors(j):
@sum(warehouse(i): volume(i,j))=demand(j));
!产量约束;
@for(warehouse(i):
@sum(volume(j): warehousw(i,j))<=capacity(i));
!这里是数据;
data:
capacity=7 4 9;
demand=3 6 5 6;
cost=3 11 3 10
1 9 2 8
7 4 10 5;
enddata
end