lingo，求代码错误原因，这段代码哪里不对，求指点帮助！

middlec/1..8/:c;
Cooperationv(middlen,middleb):v;

Cooperationx(middlen,middlem):x;

endsets
data:
x=
1
1
1
1
1
1
1
1
1
1
1;

n=
16920 0 0 0 0 0 0 0 0 0 0;
c=
5640
5640
5462
4852
4562
1532
4265
4555;
b=
2.03713000000000
0.992890000000000
0.100350000000000
0.557560000000000
0.0579700000000000
0.0214500000000000
1.10413000000000
0.322040000000000;

enddata
min=m(h);
m(h)=@sum(middlew(t):w(t)*b(t));
@for(middlew(t):w(t)=@sum(middlen(r):n(r)*v(r,t)));

@for(Cooperationv(u,y):@bin(v));

@for(middleb(y):p(y)=@sum(middlen(r):n(r)*v(r,y)));
@for(middleb(y):p(y)<=c(y));

@for(middlen(r):(@sum(middleb(t):v(r,t))=x(r)));
end

错误原因显示：missing right parenthesis.
61] 后为61行代码

同学你好，提示说你的那一行出现了右括号缺失的问题，把那行改成下面这种就可以啦！

@for(middlen(r):(@sum(middleb(t):v(r,t)))=x(r));