bzoj3244

很不幸，这题我又被虐了，给个链接http://www.cnblogs.com/g-word/p/3288675.html

 var p:array[..] of longint;
     f:array[..,..] of longint;
     mx,b,d,v:array[..] of longint;
     i,j,n,k:longint;
     ans,s:double;

 function min(a,b:longint):longint;
   begin
     if a>b then exit(b) else exit(a);
   end;

 function ask(l,r:longint):longint;
   begin
     k:=trunc(ln(r-l+)/ln()+0.0001);
     exit(min(f[l,k],f[r-p[k]+,k]));
   end;

 begin
   readln(n);
   for i:= to n do
     read(d[i]);
   for i:= to n do
   begin
     read(b[i]);
     v[b[i]]:=i;
   end;
   for i:= to n do
     d[i]:=v[d[i]];
   for i:= to n do
   begin
     v[d[i]]:=i;
     if mx[i-]>d[i] then mx[i]:=mx[i-] else mx[i]:=d[i];
     f[i,]:=d[i];
   end;
   k:=trunc(ln(n)/ln()+0.1);
   p[]:=;
   for i:= to k do
     p[i]:=p[i-]*;
   for j:= to k do
     for i:= to n do
       if i+p[j]-<=n then
         f[i,j]:=min(f[i,j-],f[i+p[j-],j-])
       else break;
   ans:=;
   for i:= to n- do
     if (i=) or (v[i]>v[i+]) then ans:=ans++s
     else if (v[i+]=v[i]+) and (mx[v[i]]<=i+) then s:=s+0.5
     else if ask(v[i],v[i+])<i then s:=;
   ans:=ans+s;
   writeln(ans-0.001::);
   writeln(ans::);
   writeln(ans+0.001::);
 end.