BZOJ3224 普通平衡树 with FHQ Treap

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学了FHQTreap来试试模板，发现就这道题我的代码而言，比Treap和Scp慢，比Splay快。 当然一年过去了代码风格也有变化，等有空把各种平衡树的性能测试一番。

Code

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//Code by Lucida
#include<bits/stdc++.h>
#define red(x) scanf("%d",&x)
//#define debug(x) std::cout<<#x<<'='<<x<<std::endl
template <class T> inline bool chkmx(T &a,const T &b){return a<b?a=b,1:0;}
template <class T> inline bool chkmn(T &a,const T &b){return a>b?a=b,1:0;}
const int MAXN=100000+10,P=1e5+7,INF=0x1f1f1f1f;
using std::pair;
using std::make_pair;
struct TreapNode
{
	TreapNode *son[2];
	int py,v,sz;
	void up(){sz=1+son[0]->sz+son[1]->sz;}
	int Rank(int);
	int LowCount(int);
	int Kth(int);
	int Pred(int);
	int Succ(int);
}*null=new TreapNode,*root=null;
typedef pair<TreapNode*,TreapNode*> NodePair;
inline void InitTreap()
{
	null->son[0]=null->son[1]=null;
	null->py=P;null->sz=null->v=0;
}
inline TreapNode *newTreapNode(int v)
{
	static TreapNode *ME=new TreapNode[MAXN],*cur;
	cur=ME++;cur->v=v;cur->son[0]=cur->son[1]=null;
	cur->py=rand()%P;cur->sz=1;
	return cur;
}
TreapNode *Merge(TreapNode *a,TreapNode *b)
{
	if(a==null) return b;
	if(b==null) return a;
	if(a->py<b->py)
	{
		a->son[1]=Merge(a->son[1],b);
		a->up();
		return a;
	}
	else//a->val>b->val
	{
		b->son[0]=Merge(a,b->son[0]);
		b->up();
		return b;
	}
}
NodePair Split(TreapNode *pos,int K)
{
	NodePair cur=make_pair(null,null);
	if(pos==null) return cur;
	if(K<=pos->son[0]->sz)
	{
		cur=Split(pos->son[0],K);
		pos->son[0]=cur.second,pos->up();
		cur.second=pos;
	}
	else
	{
		cur=Split(pos->son[1],K-pos->son[0]->sz-1);
		pos->son[1]=cur.first,pos->up();
		cur.first=pos;
	}
	return cur;
}
void Insert(int x)
{
	NodePair sp=Split(root,root->LowCount(x));
	root=Merge(Merge(sp.first,newTreapNode(x)),sp.second);
}
void Delete(int x)
{
	NodePair sp1=Split(root,root->LowCount(x)),
			 sp2=Split(sp1.second,sp1.second->Rank(x));
	root=Merge(sp1.first,sp2.second);
}
int TreapNode::LowCount(int v)
{
	TreapNode *pos=this;
	int res=0;
	while(pos!=null)
	{
		if(pos->v<v)
		{
			res+=pos->son[0]->sz+1;
			pos=pos->son[1];
		}
		else
			pos=pos->son[0];
	}
	return res;
}
int TreapNode::Rank(int v){return LowCount(v)+1;}
int TreapNode::Kth(int K)
{
	TreapNode *pos=this;
	while(pos!=null)
	{
		if(pos->son[0]->sz+1==K) return pos->v;
		else if(K<pos->son[0]->sz+1) pos=pos->son[0];
		else K-=pos->son[0]->sz+1,pos=pos->son[1];
	}
	return INF;
}
int TreapNode::Pred(int x)
{
	TreapNode *pos=this;
	int res=-INF;
	while(pos!=null)
	{
		if(pos->v<x)
		{
			chkmx(res,pos->v);
			pos=pos->son[1];
		}
		else
			pos=pos->son[0];
	}
	return res;
}
int TreapNode::Succ(int x)
{
	TreapNode *pos=this;
	int res=INF;
	while(pos!=null)
	{
		if(pos->v>x)
		{
			chkmn(res,pos->v);
			pos=pos->son[0];
		}
		else
			pos=pos->son[1];
	}
	return res;
}
int main()
{
	srand(0x1f1f1f1f);
	InitTreap();
	//freopen("input","r",stdin);
	int n;red(n);int g=0;
	for(int i=1;i<=n;i++)
	{
		int opt,x;red(opt),red(x);
		switch(opt)
		{
			case 1:Insert(x);break;
			case 2:Delete(x);break;
			case 3:printf("%d\n",root->Rank(x));break;
			case 4:printf("%d\n",root->Kth(x));break;
			case 5:printf("%d\n",root->Pred(x));break;
			case 6:printf("%d\n",root->Succ(x));break;
		}
	}
	return 0;
}