bzoj3165 1568

1568是3165的弱化版，发的代码是3165的
这道题完全没想出来，是看wyl大神的题解http://hi.baidu.com/wyl8899/item/2deafd3a376ef2d46d15e998
对我完全是一个思维上的突破，之前线段树打的标记基本都是代表整个区间的性质
而这道题区间上的标记只是部分优的线段，通过从叶子一步一步的走到根，得出这个点的最大值

 const n=;
       p=;
 type node=record
        k,b:double;
      end;

 var tree:array[..*n] of longint;
     a:array[..] of node;
     ans,x0,x1,y0,y1,t,m,ch:longint;

 procedure swap(var a,b:longint);
   var c:longint;
   begin
     c:=a;
     a:=b;
     b:=c;
   end;

 function cal(i,x:longint):double;
   begin
     exit(a[i].k*x+a[i].b);
   end;

 procedure ins(i,l,r,k:longint);
   var m:longint;
       p:double;
   begin
     if tree[i]= then
     begin
       tree[i]:=k;
       exit;
     end;
     if cal(k,l)>cal(tree[i],l) then swap(tree[i],k);
     if (l=r) or (a[tree[i]].k=a[k].k) then exit;
     p:=(a[tree[i]].b-a[k].b)/(a[k].k-a[tree[i]].k);
     if (p<l) or (p>r) then exit;
     m:=(l+r) shr ;
     if (p<=m) then
     begin
       ins(i*,l,m,tree[i]);
       tree[i]:=k;
     end
     else ins(i*+,m+,r,k);
   end;

 procedure work(i,l,r:longint);
   var m:longint;
   begin
     if (x0<=l) and (x1>=r) then
       ins(i,l,r,t)
     else begin
       m:=(l+r) shr ;
       if x0<=m then work(i*,l,m);
       if m<x1 then work(i*+,m+,r);
     end;
   end;

 function ask(i,l,r:longint):longint;
   var m,p:longint;
   begin
     if l=r then exit(tree[i])
     else begin
       m:=(l+r) shr ;
       if x0<=m then p:=ask(i*,l,m)
       else p:=ask(i*+,m+,r);
       if cal(p,x0)>cal(tree[i],x0) then exit(p) else exit(tree[i]);
     end;
   end;

 begin
   readln(m);
   while m> do
   begin
     dec(m);
     read(ch);
     if ch= then
     begin
       readln(x0,y0,x1,y1);
       x0:=(x0+ans-) mod n+;
       x1:=(x1+ans-) mod n+;
       y0:=(y0+ans-) mod p+;
       y1:=(y1+ans-) mod p+;
       if x0>x1 then
       begin
         swap(x0,x1);
         swap(y0,y1);
       end;
       inc(t);
       if x0<>x1 then
       begin
         a[t].k:=(y1-y0)/(x1-x0);
         a[t].b:=y1-a[t].k*x1;
       end
       else begin
         if y1>y0 then a[t].b:=y1 else a[t].b:=y0;
       end;
       work(,,n);
     end
     else begin
       readln(x0);
       x0:=(x0+ans-) mod n+;
       ans:=ask(,,n);
       writeln(ans);
     end;
   end;
 end.