二分图最佳匹配（网络流）

var t,ii,i,j,n,cost,top,tail,min,tt,ttf:longint;
    pre,d:array[1..1000]of longint;
    b:array[1..10000]of longint;
    flag:array[1..1000]of boolean;
    f,c:array[1..200,1..200]of longint;
begin
 read(t);
 for ii:=1 to t do
  begin
   fillchar(f,sizeof(f),0);
   fillchar(c,sizeof(c),0);
   read(n);
   for i:=2 to n+1 do
    for j:=n+2 to n+n+1 do
     begin
      read(c[i,j]);
      c[j,i]:=-c[i,j];
      f[i,j]:=1;
      f[j,i]:=0;
     end;
   for i:=1 to n do
    for j:=1 to n do
     read(tt);

   for i:=2 to n+1 do
    begin
     c[1,i]:=0;
     c[i,1]:=0;
     f[1,i]:=1;
     f[i,1]:=0;
    end;
   for i:=n+2 to 2*n+1 do
    begin
     c[i,2*n+2]:=0;
     c[2*n+2,i]:=0;
     f[i,2*n+2]:=1;
     f[2*n+2,i]:=0;
    end;

   ttf:=0;
   cost:=0;

   while true do begin
   top:=1;tail:=1;
   b[top]:=1;
   fillchar(flag,sizeof(flag),true);
   for i:=1 to n+n+2 do d[i]:=maxlongint;
   fillchar(pre,sizeof(pre),0);
   flag[1]:=false;
   pre[1]:=-1;
   d[1]:=0;
   repeat
    for i:=1 to n+n+2 do
     if b[top]<>i then
      if f[b[top],i]>0 then
       if c[b[top],i]+d[b[top]]tail;
   if d[n+n+2]=maxlongint then break;
   i:=n+n+2;
   min:=maxlongint;
   while pre[i]<>-1 do
    begin
     if min>f[pre[i],i] then min:=f[pre[i],i];
     i:=pre[i];
    end;
   i:=n+n+2;
   while pre[i]<>-1 do
    begin
     f[i,pre[i]]:=f[i,pre[i]]+min;
     f[pre[i],i]:=f[pre[i],i]-min;
     cost:=cost+c[pre[i],i]*min;
     i:=pre[i];
    end;
    ttf:=ttf+min;
//    writeln(cost);
   end;
  writeln(cost*cost);
//  writeln(ttf);
 end;
 readln;readln;
end.

加一个源点连向所有左边的点，加一个汇点连向所有右边的点，边的费用为0，流量为1。

中间的边费用为c，流量为1