无旋Treap

最新推荐文章于 2024-12-07 23:57:18 发布

weixin_30416497

最新推荐文章于 2024-12-07 23:57:18 发布

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CC 4.0 BY-SA版权

原文链接：http://www.cnblogs.com/TheRoadToAu/p/8679009.html

本文分享了一个无旋Treap的数据结构实现代码，并通过不同的操作如插入、删除、查找等来演示其功能。该Treap实现了随机化的二叉搜索树，能够高效地进行元素的维护。

啊，终于敲熟了无旋Treap的板子。自己太弱了。垃圾码风吃枣药丸。（自己抄代码的能力又有提高了）

#include<cstdio>
#include<cctype>
#include<cstdlib>
using namespace std;
namespace Treap{
	const int maxn=100100,inf=0x7fffffff;
	struct Treap{
		Treap *ch[2];
#define ls ch[0]
#define rs ch[1]
		int key,val,size;
		Treap(int v){size=1,val=v,key=rand();ls=rs=0;}
		inline void tain(){size=1+(ls?ls->size:0)+(rs?rs->size:0);}
	}*root;
	typedef struct pair{Treap *first,*second;pair(Treap *_f,Treap *_s){this->first=_f,this->second=_s;}pair(){}}D;
	inline int size(Treap *o){return o?o->size:0;}
	Treap *Merge(Treap *a,Treap *b)
	{
		if(!a)return b;
		if(!b)return a;
		if(a->key>b->key){a->rs=Merge(a->rs,b),a->tain();return a;}
		b->ls=Merge(a,b->ls),b->tain();return b;
	}
	D Split(Treap *o,int k)
	{
		if(!o)return D(0,0);
		D y;
		if(size(o->ls)>=k){y=Split(o->ls,k);o->ls=y.second;o->tain();y.second=o;return y;}
		y=Split(o->rs,k-size(o->ls)-1);o->rs=y.first;o->tain();y.first=o;return y;
	}
	int Getkth(Treap *o,int v)
	{
		if(!o)return 0;
		return o->val>=v?Getkth(o->ls,v):Getkth(o->rs,v)+size(o->ls)+1;
	}
	inline int Findkth(int k)
	{
		D x=Split(root,k-1);
		D y=Split(x.second,1);
		Treap* ans=y.first;
		root=Merge(Merge(x.first,ans),y.second);
		return ans?ans->val:0;
	}
	inline void Insert(int v)
	{
		int k=Getkth(root,v);
		D x=Split(root,k);
		Treap* o=new Treap(v);
		root=Merge(Merge(x.first,o),x.second);
	}
	void Delete(int v)
	{
		int k=Getkth(root,v);
		D x=Split(root,k);
		D y=Split(x.second,1);
		root=Merge(x.first,y.second);
	}
#undef ls
#undef rs
}
namespace IO{
	const int InputBufferSize = 67108864;//输入缓冲区大小
	const int OutputBufferSize = 67108864;//输出缓冲区大小
	namespace input{
    	char buffer[InputBufferSize],*s,*eof;
    	inline void init()
    	{
        	s=buffer;
        	eof=s+fread(buffer,1,InputBufferSize,stdin);
    	}
    	inline bool read(int &x)
    	{
	        while(!isdigit(*s)&&*s!='-')s++;
	        if(eof<=s)return false;
	        x=0;
	        register int flag=1;
	        if(*s=='-')flag=-1,s++;
 	        while(isdigit(*s))x=x*10+*s++-'0';
 	        x*=flag;
	        return true;
    	}
	    inline bool read(char *str)
    	{
        	*str=0;
	        while(isspace(*s))s++;
    	    if(eof<s)return false;
        	while(!isspace(*s))*str=0,*str=*s,str++,s++;
        	*str=0;
        	return true;
    	}
	}
	namespace output{
    	char buffer[OutputBufferSize];
    	char *s=buffer;
    	inline void flush()
	    {
        	fwrite(buffer,1,s-buffer,stdout);
        	s=buffer;
    	}
    	inline void print(const char ch)
	    {
    	    if(s-buffer>OutputBufferSize-2)flush();
        	*s++=ch;
	    }
    	inline void print(char *str)){while(*str!=0)print(char(*str++));}
    	inline void print(int x)
    	{
        	char buf[25]= {0},*p=buf;
        	if(x<0)print('-'),x=-x;
    	    if(x==0)print('0');
	        while(x)*(++p)=x%10,x/=10;
        	while(p!=buf)print(char(*(p--)+'0'));
    	}
	}
	using namespace input;
	using namespace output;
}
using namespace IO;
using namespace Treap;
int main()
{
    init();
    int m,opt,x;read(m);
    while(m--)
    {
        read(opt);read(x);
        switch(opt)
        {
            case 1:Insert(x);break;
            case 2:Delete(x);break;
            case 3:print(Getkth(root,x)+1);print('\n');break;
            case 4:print(Findkth(x));print('\n');break;
            case 5:print(Findkth(Getkth(root,x)));print('\n');break;
            case 6:print(Findkth(Getkth(root,x+1)+1));print('\n');break;
        }
    }
    flush();
    return 0;
}

　　读入优化在哪里都能用，开心。

转载于:https://www.cnblogs.com/TheRoadToAu/p/8679009.html