bzoj1565

很明显是最大权闭合子图，但要注意
互相保护的植物打不掉，被互相保护的植物所直接或间接保护的植物也打不掉
我们先拓扑排序然后dfs出能打掉的点，然后做最大权闭合子图

 const inf=;
 type node=record
        po,flow,next:longint;
      end;
 
 var e,w:array[..] of node;
     num:array[..,..] of longint;
     cur,pre,p,st,q,numh,s,h,d:array[..] of longint;
     can,v:array[..] of boolean;
     n,m,i,j,x,y,len,k,t,f:longint;
 
 function min(a,b:longint):longint;
   begin
     if a>b then exit(b) else exit(a);
   end;
 
 procedure add(x,y:longint);
   begin
     inc(len);
     w[len].po:=y;
     inc(d[y]);
     w[len].next:=q[x];
     q[x]:=len;
   end;
 
 procedure ins(x,y,f:longint);
   begin
     inc(len);
     e[len].po:=y;
     e[len].flow:=f;
     e[len].next:=p[x];
     p[x]:=len;
   end;
 
 procedure build(x,y,f:longint);
   begin
     ins(x,y,f);
     ins(y,x,);
   end;
 
 procedure dfs(x:longint);
   var i,y:longint;
   begin
     v[x]:=true;
     can[x]:=false;
     i:=q[x];
     while i<> do
     begin
       y:=w[i].po;
       if not v[y] then dfs(y);
       i:=w[i].next;
     end;
   end;
 
 function sap:longint;
   var i,j,u,tmp,neck,q:longint;
   begin
     u:=;
     sap:=;
     for i:= to t do
       cur[i]:=p[i];
     numh[]:=t+;
     neck:=inf;
     while h[]<t+ do
     begin
       i:=cur[u];
       d[u]:=neck;
       while i<>- do
       begin
         j:=e[i].po;
         if (e[i].flow>) and (h[u]=h[j]+) then
         begin
           neck:=min(neck,e[i].flow);
           cur[u]:=i;
           pre[j]:=u;
           u:=j;
           if u=t then
           begin
             sap:=sap+neck;
             while u<> do
             begin
               u:=pre[u];
               j:=cur[u];
               dec(e[j].flow,neck);
               inc(e[j xor ].flow,neck);
             end;
             neck:=inf;
           end;
           break;
         end;
         i:=e[i].next;
       end;
       if i=- then
       begin
         dec(numh[h[u]]);
         if numh[h[u]]= then exit;
         q:=-;
         tmp:=t;
         i:=p[u];
         while i<>- do
         begin
           j:=e[i].po;
           if e[i].flow> then
             if h[j]<tmp then
             begin
               q:=i;
               tmp:=h[j];
             end;
           i:=e[i].next;
         end;
         h[u]:=tmp+;
         inc(numh[h[u]]);
         cur[u]:=q;
         if u<> then
         begin
           u:=pre[u];
           neck:=d[u];
         end;
       end;
     end;
   end;
 
 begin
   readln(n,m);
   for i:= to n- do
     for j:= to m- do
     begin
       inc(k);
       num[i,j]:=k;
     end;
 
   for i:= to n*m do
   begin
     read(s[i],k);
     for j:= to k do
     begin
       read(x,y);
       add(i,num[x,y]);
     end;
   end;
   for i:= to n do
     for j:=m- downto  do
       add(num[i,j],num[i,j-]);
 
   f:=; t:=;
   for i:= to n*m do
     if d[i]= then
     begin
       inc(t);
       st[t]:=i;
     end;
 
   while f<=t do
   begin
     x:=st[f];
     can[x]:=true;
     i:=q[x];
     while i<> do
     begin
       y:=w[i].po;
       dec(d[y]);
       if d[y]= then
       begin
         inc(t);
         st[t]:=y;
       end;
       i:=w[i].next;
     end;
     inc(f);
   end;
   for i:= to n*m do
     if not can[i] then
     begin
       fillchar(v,sizeof(v),false);
       dfs(i);
     end;
   t:=n*m+; k:=; len:=-;
   fillchar(p,sizeof(p),);
   for i:= to n*m do
     if can[i] then
     begin
       if s[i]> then
       begin
         build(,i,s[i]);
         k:=k+s[i];
       end
       else build(i,t,-s[i]);
       j:=q[i];
       while j<> do
       begin
         y:=w[j].po;
         if can[y] then build(y,i,inf);
         j:=w[j].next;
       end;
     end;
   writeln(k-sap);
 end.