[BZOJ1208] [HNOI2004]宠物收养所

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题目大意

题解

const
maxn=100005;
var
w:array[1..2,-1..maxn,1..6]of longint;
sum,root:array[1..2]of longint;
i,j,k:longint;
n,a,b:longint;
ans,c,d:int64;
procedure print(key,a:longint);
begin
if w[key,a,1]<>-1 then print(key,w[key,a,1]);
write(w[key,a,6],' ');
if w[key,a,2]<>-1 then print(key,w[key,a,2]);
if a=root[key] then writeln;
end;

procedure rotate(key,a,kind:longint);
var b,unkind:longint;
begin
b:=w[key,a,3]; unkind:=kind xor 3;
w[key,a,4]:=w[key,b,4]; dec(w[key,b,4],w[key,a,5]+w[key,w[key,a,kind],4]);
w[key,w[key,a,unkind],3]:=b; w[key,b,kind]:=w[key,a,unkind];
w[key,a,unkind]:=b; w[key,a,3]:=w[key,b,3]; w[key,b,3]:=a;
if w[key,a,3]<>-1
then
if w[key,w[key,a,3],1]=b
then w[key,w[key,a,3],1]:=a
else w[key,w[key,a,3],2]:=a;
end;

procedure splay(key,a,goal:longint);
var b,kind,unkind:longint;
begin
while w[key,a,3]<>goal do
begin
b:=w[key,a,3]; if w[key,b,1]=a then kind:=1 else kind:=2; unkind:=kind xor 3;
if w[key,b,3]=goal then rotate(key,a,kind)
else
if w[key,w[key,b,3],kind]=b
then begin rotate(key,b,kind); rotate(key,a,kind); end
else begin rotate(key,a,kind); rotate(key,a,unkind); end
end;
if goal=-1 then root[key]:=a;
end;

procedure init(key,a:longint);
var tt,fa,kind:longint;
begin
tt:=root[key];
while tt<>-1 do
begin
inc(w[key,tt,4]); fa:=tt;
if w[key,tt,6]=a then break;
if a<w[key,tt,6]
then begin tt:=w[key,tt,1]; kind:=1; end
else begin tt:=w[key,tt,2]; kind:=2; end;
end;
if tt<>-1
then begin inc(w[key,tt,5]); splay(key,tt,-1); end
else begin inc(sum[key]); w[key,sum[key],1]:=-1; w[key,sum[key],2]:=-1; w[key,sum[key],3]:=fa; w[key,sum[key],4]:=1; w[key,sum[key],5]:=1; w[key,sum[key],6]:=a; w[key,fa,kind]:=sum[key]; splay(key,sum[key],-1); end;
end;

function getmax(key,a:longint):longint;
var tt:longint;
begin
tt:=a;
while w[key,tt,2]<>-1 do
tt:=w[key,tt,2];
exit(tt);
end;

function getmin(key,a:longint):longint;
var tt:longint;
begin
tt:=a;
while w[key,tt,1]<>-1 do
tt:=w[key,tt,1];
exit(tt);
end;

procedure del(key,a:longint);
var tt:longint;
begin
tt:=root[key];
while w[key,tt,6]<>a do
if a<w[key,tt,6]
then tt:=w[key,tt,1]
else tt:=w[key,tt,2];
splay(key,tt,-1);
if w[key,tt,5]=1
then begin
splay(key,getmax(key,w[key,root[key],1]),root[key]);
w[key,w[key,root[key],1],2]:=w[key,root[key],2];
root[key]:=w[key,root[key],1];
w[key,root[key],3]:=-1;
w[key,w[key,root[key],2],3]:=root[key];
inc(w[key,root[key],4],w[key,w[key,root[key],2],4]);end
else begin dec(w[key,tt,4]); dec(w[key,tt,5]); end;
end;

begin
readln(n); ans:=0;
root[1]:=1; sum[1]:=1;
w[1,1,1]:=-1; w[1,1,2]:=-1; w[1,1,3]:=-1; w[1,1,4]:=1; w[1,1,5]:=1; w[1,1,6]:=-1000000000;
root[2]:=1; sum[2]:=1;
w[2,1,1]:=-1; w[2,1,2]:=-1; w[2,1,3]:=-1; w[2,1,4]:=1; w[2,1,5]:=1; w[2,1,6]:=-1000000000;
for i:=1 to n do
begin
readln(a,b);
if a=0
then begin
if w[2,root[2],4]>=2
then begin
init(2,b);
if w[2,root[2],5]>=3
then del(2,b)
else begin
c:=100000000000; d:=100000000000;
if w[2,w[2,root[2],1],4]>=2
then c:=w[2,getmax(2,w[2,root[2],1]),6];
if w[2,w[2,root[2],2],4]>=1
then d:=w[2,getmin(2,w[2,root[2],2]),6];
if abs(c-b)<=abs(d-b)
then begin ans:=(ans+abs(c-b))mod 1000000; del(2,c); end
else begin ans:=(ans+abs(d-b))mod 1000000; del(2,d); end;
del(2,b);
end;
end
else init(1,b);
end
else begin
if w[1,root[1],4]>=2
then begin
init(1,b);
if w[1,root[1],5]>=3
then del(1,b)
else begin
c:=100000000000; d:=100000000000;
if w[1,w[1,root[1],1],4]>=2
then c:=w[1,getmax(1,w[1,root[1],1]),6];
if w[1,w[1,root[1],2],4]>=1
then d:=w[1,getmin(1,w[1,root[1],2]),6];
if abs(c-b)<=abs(d-b)
then begin ans:=(ans+abs(c-b))mod 1000000; del(1,c); end
else begin ans:=(ans+abs(d-b))mod 1000000; del(1,d); end;
del(1,b);
end;
end
else init(2,b);
end;
end;
writeln(ans);
end.