【BZOJ3165】[HEOI2013]Segment(李超线段树)

【BZOJ3165】[HEOI2013]Segment(李超线段树)

题面

BZOJ
洛谷

题解

似乎还是模板题QwQ

#include<iostream>
#include<cstdio>
#include<cmath>
using namespace std;
#define MAX 100100
#define lson (now<<1)
#define rson (now<<1|1)
inline int read()
{
	int x=0;bool t=false;char ch=getchar();
	while((ch<'0'||ch>'9')&&ch!='-')ch=getchar();
	if(ch=='-')t=true,ch=getchar();
	while(ch<='9'&&ch>='0')x=x*10+ch-48,ch=getchar();
	return t?-x:x;
}
int N=100000;
struct Node
{
	bool fl;int id;double k,b;
	void upd(int _id,double _k,double _b){id=_id,k=_k;b=_b;}
}t[MAX<<2];
double K[MAX],B[MAX];
void Modify(int now,int l,int r,int id,double k,double b)
{
	if(!t[now].fl){t[now].fl=true;t[now].upd(id,k,b);return;}
	int mid=(l+r)>>1;
	double l1=l*t[now].k+t[now].b,r1=r*t[now].k+t[now].b;
	double l2=l*k+b,r2=r*k+b;
	if(l1>=l2&&r1>=r2)return;
	if(l2>l1&&r2>r1){t[now].upd(id,k,b);return;}
	double x=(t[now].b-b)/(k-t[now].k);
	if(x<=mid)
	{
		if(l1>l2)Modify(lson,l,mid,t[now].id,t[now].k,t[now].b),t[now].upd(id,k,b);
		else Modify(lson,l,mid,id,k,b);
	}
	else
	{
		if(l1>l2)Modify(rson,mid+1,r,id,k,b);
		else Modify(rson,mid+1,r,t[now].id,t[now].k,t[now].b),t[now].upd(id,k,b);
	}
}
void Modify(int now,int l,int r,int L,int R,int id,double k,double b)
{
	if(L<=l&&r<=R){Modify(now,l,r,id,k,b);return;}
	int mid=(l+r)>>1;
	if(L<=mid)Modify(lson,l,mid,L,R,id,k,b);
	if(R>mid)Modify(rson,mid+1,r,L,R,id,k,b);
}
void Cmax(int &a,int b,int x)
{
	double ya=K[a]*x+B[a];
	double yb=K[b]*x+B[b];
	if(ya<yb||(fabs(ya-yb)<1e-7&&a>b))a=b;
}
int Query(int now,int l,int r,int x)
{
	if(l==r)return t[now].id;
	int mid=(l+r)>>1,ret=t[now].id;
	if(x<=mid)Cmax(ret,Query(lson,l,mid,x),x);
	else Cmax(ret,Query(rson,mid+1,r,x),x);
	return ret;
}
int Q,ans,tot;
int main()
{
	Q=read();
	while(Q--)
	{
		int opt=read();
		if(!opt)
		{
			int x=((read()+ans-1)%39989+1);
			ans=Query(1,1,N,x);
			printf("%d\n",ans);
		}
		else
		{
			int x0=(read()+ans-1)%39989+1,y0=(read()+ans-1)%1000000000+1;
			int x1=(read()+ans-1)%39989+1,y1=(read()+ans-1)%1000000000+1;
			if(x0>x1)swap(x0,x1),swap(y0,y1);
			++tot;K[tot]=1.0*(y0-y1)/(x0-x1);B[tot]=y0-K[tot]*x0;
			Modify(1,1,N,x0,x1,tot,K[tot],B[tot]);
		}
	}
	return 0;
}
posted @ 2019-03-19 20:05  小蒟蒻yyb  阅读(1101)  评论(2编辑  收藏  举报