bzoj1251: 序列终结者 (splay)

{$inline on}
{$M 1000000000,0,maxlongint}
const
  //mm=maxlongint>>2;
  maxn=60000;
 
var
  size,left,right,mark,fa,value,max:array[0..maxn]of longint;
  rev:array[0..maxn]of boolean;
  root,i,j,k,l,n,m,tot,x:longint;
 
function new:longint;inline;
begin
  inc(tot);
  exit(tot);
end;
 
function mmax(x,y:longint):longint;inline;
begin
  if x<y then exit(y);
  exit(x)
end;

procedure swap(var x,y:longint);inline;
var
  i:longint;
begin
  i:=x;
  x:=y;
  y:=i;
end;

procedure pushdown(x:longint);inline;
begin
  if x=0 then exit;
  if rev[x] then begin
    swap(left[x],right[x]);
    rev[left[x]]:=rev[left[x]] xor true;
    rev[right[x]]:=rev[right[x]] xor true;
    rev[x]:=false;
  end;
  if mark[x]<>0 then begin
    value[x]:=value[x]+mark[x];
    max[x]:=max[x]+mark[x];
    inc(mark[left[x]],mark[x]);
    inc(mark[right[x]],mark[x]);
    mark[x]:=0;
  end;
end;

procedure update(x:longint);inline;
begin
  pushdown(x);
  pushdown(left[x]);
  pushdown(right[x]);
  size[x]:=size[left[x]]+size[right[x]]+1;
  max[x]:=mmax(value[x],mmax(max[left[x]],max[right[x]]));
end;
 
procedure lt(x:longint);inline;
var
  u,k:longint;
  flag:boolean;
begin
  pushdown(x);
  pushdown(right[x]);
  k:=right[x];
  u:=fa[x];
  if left[u]=x then flag:=true else flag:=false;
  right[x]:=left[k];
  fa[right[x]]:=x;
  left[k]:=x;
  fa[x]:=k;
  update(x);
  update(k);
  fa[k]:=u;
  if flag then left[u]:=k else right[u]:=k;
end;
 
procedure rt(x:longint);inline;
var
  u,k:longint;
  flag:boolean;
begin
  pushdown(x);
  pushdown(left[x]);
  k:=left[x];
  u:=fa[x];
  if left[u]=x then flag:=true else flag:=false;
  left[x]:=right[k];
  fa[left[x]]:=x;
  right[k]:=x;
  fa[x]:=k;
  update(x);
  update(k);
  fa[k]:=u;
  if flag then left[u]:=k else right[u]:=k;
end;
 
procedure splay(x,u:longint);inline;
begin
  while fa[x]<>u do begin
    if fa[fa[x]]=u then begin
      if left[fa[x]]=x then rt(fa[x])
        else lt(fa[x]);
      exit;
    end;
    if left[fa[x]]=x then begin
      if left[fa[fa[x]]]=fa[x] then rt(fa[fa[x]]);
      rt(fa[x]);
    end
    else begin
      if right[fa[fa[x]]]=fa[x] then lt(fa[fa[x]]);
      lt(fa[x]);
    end;
  end;
end;
 
function find(x,y:longint):longint;inline;
begin
  pushdown(x);
  if size[left[x]]=y-1 then exit(x);
  if y<=size[left[x]] then exit(find(left[x],y))
    else exit(find(right[x],y-1-size[left[x]]));
end;
 
 
function change(j,k:longint):longint;inline;
var
  now:longint;
begin
  now:=find(root,j);
  splay(now,0);
  root:=now;
  now:=find(root,k+2);
  splay(now,root);
  exit(now);
end;
 
function build(l,r:longint):longint;inline;
var
  mid,x:longint;
begin
  mid:=(l+r)>>1;
  x:=new;
  value[x]:=0;
  size[x]:=r-l+1;
  rev[x]:=false;
  mark[x]:=0;
  left[x]:=0;
  right[x]:=0;
  if l=r then begin
    if (l=0) or (l=n+1) then value[x]:=-maxlongint>>1;
    max[x]:=value[x];
    exit(x);
  end;
  if l<mid then begin
    left[x]:=build(l,mid-1);
    fa[left[x]]:=x;
  end;
  if mid<r then begin
    right[x]:=build(mid+1,r);
    fa[right[x]]:=x;
  end;
  update(x);
  exit(x);
end;

begin
  readln(n,m);
  max[0]:=-maxlongint;
  root:=build(0,n+1);
  while m>0 do begin
    dec(m);
    read(j);
    if j=1 then begin
      readln(j,k,l);
      x:=change(j,k);
      inc(mark[left[x]],l);
      update(x);
      update(root);
    end
    else
    if j=2 then begin
      readln(j,k);
      x:=change(j,k);
      rev[left[x]]:=rev[left[x]] xor true;
      update(x);
      update(root);
    end
    else begin
      readln(j,k);
      x:=change(j,k);
      writeln(max[left[x]]);
    end;
  end;
end.