bzoj3571

同样的最小乘积XXX模型，这里显然是二分图带权匹配

我不会写KM……于是写了个费用流，由于是稠密图，会退化到n^4

然后本地跑了56s，交上去过了………………一定是我电脑太慢……

改天写个KM吧

 const inf=*;
 type node=record
        po,next,flow,cost:longint;
      end;
      point=record
        x,y:longint;
      end;

 var e:array[..] of node;
     ma,pre,cur,p,d:array[..] of longint;
     v:array[..] of boolean;
     a,b,c:array[..,..] of longint;
     q:array[..] of longint;
     j,len,i,tt,t,n,ans:longint;
     p1,p2:point;

 procedure add(x,y,f,c:longint);
   begin
     inc(len);
     e[len].po:=y;
     e[len].flow:=f;
     e[len].cost:=c;
     e[len].next:=p[x];
     p[x]:=len;
   end;

 procedure build(x,y,f,c:longint);
   begin
     add(x,y,f,c);
     add(y,x,,-c);
   end;

 function spfa:boolean;
   var f,r,x,y,i,j:longint;
   begin
     fillchar(v,sizeof(v),false);
     for i:= to t do
       d[i]:=inf;
     d[]:=;
     f:=;
     r:=;
     q[]:=;
     while f<=r do
     begin
       x:=q[f];
       v[x]:=false;
       i:=p[x];
       while i<>- do
       begin
         y:=e[i].po;
         if e[i].flow> then
           if d[x]+e[i].cost<d[y] then
           begin
             d[y]:=d[x]+e[i].cost;
             cur[y]:=i;
             pre[y]:=x;
             if not v[y] then
             begin
               inc(r);
               q[r]:=y;
               v[y]:=true;
             end;
           end;
         i:=e[i].next;
       end;
       inc(f);
     end;
     if d[t]=inf then exit(false) else exit(true);
   end;

 procedure change(j:longint);
   begin
     dec(e[j].flow);
     inc(e[j xor ].flow);
   end;

 function get:point;
   var i,j,x,y:longint;
   begin
     len:=-;
     fillchar(p,sizeof(p),);
     for i:= to n do
     begin
       build(,i,,);
       build(i+n,t,,);
     end;
     x:=; y:=;
     for i:= to n do
       for j:= to n do
       begin
         build(i,j+n,,c[i,j]);
         if c[i,j]<c[x,y] then
         begin
           x:=i;
           y:=j;
         end;
       end;
     ma[y+n]:=x;
     i:=p[x];
     while i<>- do
     begin
       if (e[i].po=y+n) then change(i);
       if e[i].po= then change(i xor );
       i:=e[i].next;
     end;
     i:=p[y+n];
     while i<>- do
     begin
       if e[i].po=t then
       begin
         change(i);
         break;
       end;
       i:=e[i].next;
     end;
     while spfa do
     begin
       i:=t;
       while i<> do
       begin
         j:=cur[i];
         change(j);
         if (i>n) and (i<>t) then
           ma[i]:=pre[i];
         i:=pre[i];
       end;
     end;
     get.x:=; get.y:=;
     for i:= to n do
     begin
       j:=ma[i+n];
      // write(j,' ');
       inc(get.x,a[j,i]);
       inc(get.y,b[j,i]);
     end;
    // writeln;
     if get.x*get.y<ans then ans:=get.x*get.y;
   end;

 function cross(a,b,c:point):longint;
   begin
     exit((a.x-c.x)*(b.y-c.y)-(a.y-c.y)*(b.x-c.x));
   end;

 procedure work(p1,p2:point);
   var p:point;
       i,j:longint;
   begin
     for i:= to n do
       for j:= to n do
         c[i,j]:=a[i,j]*(p1.y-p2.y)+b[i,j]*(p2.x-p1.x);
     p:=get;
     if cross(p2,p,p1)>= then exit;
     work(p1,p);
     work(p,p2);
   end;

 begin
   readln(tt);
   while tt> do
   begin
     dec(tt);
     readln(n);
     t:=*n+;
     for i:= to n do
       for j:= to n do
         read(a[i,j]);
     for i:= to n do
       for j:= to n do
         read(b[i,j]);
     for i:= to n do
       for j:= to n do
         c[i,j]:=a[i,j];
     ans:=*;
     p1:=get;
     for i:= to n do
       for j:= to n do
         c[i,j]:=b[i,j];
     p2:=get;
     work(p1,p2);
     writeln(ans);
   end;
 end.