POJ 2823(双端队列）

这题考双端队列……好偏门的数据结构……

Program c;
const
    maxn=1000000;
type
   node=record
        num,d:longint;
        end;
   douq=record
        d:array[1..maxn] of node;
        l,r:longint;
        end;

var
   n,k,i,j:longint;
   a:array[1..maxn] of longint;
   ans1,ans2:array[1..maxn] of longint;
   minq,maxq:douq;
procedure push(var q:douq;num2,d2:longint);
begin
   with q do
   begin
      inc(r);
      d[q.r].num:=num2;
      d[q.r].d:=d2;
   end;
end;
procedure popl(var q:douq;i:longint);
begin
   with q do
   begin
      if d[l].num=i then inc(l);
   end;
end;
procedure popr(up,i:longint);
var
   j:longint;
begin
   if up=1 then
   begin
      with minq do
      begin
         while (l<r) and (d[r].d>i) do dec(r);
         if l=r then
         if d[r].d>i then dec(r);

      end;
   end
   else
   begin
      with maxq do
      begin
         while (l<r) and (d[r].d<i) do dec(r);
         if l=r then
         if d[r].d<i then dec(r);
      end;

   end;
end;
begin
   read(n,k);
   for i:=1 to n do read(a[i]);
   fillchar(minq,sizeof(minq),0);
   minq.l:=1;
   fillchar(maxq,sizeof(maxq),0);
   maxq.l:=1;
   if k=1 then
   begin
      for i:=1 to n-1 do write(a[i],' ');
      writeln(a[n]);
      for i:=1 to n-1 do write(a[i],' ');
      writeln(a[n]);
   end
   else
   begin
      for i:=1 to k do
      begin
         popr(1,a[i]);
         push(minq,i,a[i]);
         popr(0,a[i]);
         push(maxq,i,a[i]);
      end;
      ans1[1]:=minq.d[minq.l].d;
      ans2[1]:=maxq.d[maxq.l].d;
      for i:=k+1 to n do
      begin
         popl(minq,i-k);
         popl(maxq,i-k);
         popr(1,a[i]);
         push(minq,i,a[i]);
         popr(0,a[i]);
         push(maxq,i,a[i]);
         ans1[i-k+1]:=minq.d[minq.l].d;
         ans2[i-k+1]:=maxq.d[maxq.l].d;


      end;
      for i:=1 to n-k do write(ans1[i],' ');
      writeln(ans1[n-k+1]);
      for i:=1 to n-k do write(ans2[i],' ');
      writeln(ans2[n-k+1]);
   end;
end.