【BZOJ1123】 [POI2008]BLO （tarjan）

tarjan判断割点...拿掉一个点之后，会被分成若干个联通块，用节点个数和统计一下他们相互不能到达的个数就好。

 const maxn=;
  maxm=;
 type
  edgetype=record
   toward,next:longint;
  end;

 var
  edge:array[..maxm] of edgetype;
  first,dfn,low,stack,s:array[..maxn] of longint;
  pd:array[..maxn] of boolean;
  sum:array[..maxn] of int64;
  tot,cnt,i,n,m:longint;

 function min(x,y:longint):longint; begin if x<y then exit(x) else exit(y); end;

 procedure addedge(i,j:longint);
 begin
  inc(tot);
  edge[tot].toward:=j;
  edge[tot].next:=first[i];
  first[i]:=tot;
 end;

 procedure add(i,j:longint);
 begin
  addedge(i,j); addedge(j,i);
 end;

 procedure tarjan(v:longint);
 var i,tmp,son:longint;
 begin
  son:=;
  inc(cnt); dfn[v]:=cnt; low[v]:=cnt;
  pd[v]:=true; s[v]:=;
  i:=first[v];
  while i<> do
   begin
    tmp:=edge[i].toward;
    if dfn[tmp]= then
     begin
      tarjan(tmp);
      s[v]:=s[v]+s[tmp];
      low[v]:=min(low[v],low[tmp]);
      if dfn[v]<=low[tmp] then
       begin
        sum[v]:=sum[v]+int64(son)*s[tmp];
        inc(son,s[tmp]);
       end;
     end
    else low[v]:=min(dfn[tmp],low[v]);
    i:=edge[i].next;
   end;
  sum[v]:=sum[v]+int64(son)*(n-son-);
 end;

 procedure init;
 var i,a,b:longint;
 begin
  readln(n,m);
  for i:=  to m do
   begin
    readln(a,b);
    add(a,b);
   end;
  tarjan();
 end;

 Begin
  init;
  for i:=  to n do writeln((sum[i]+n-)<<);
 End.