[模板] 无旋Treap (C++ class)

注意！本帖不是算法介绍！只是贴代码（逃）

//嫌stdlib的rand太慢，手打了一个

 /*
     Author: hotwords
 */

 typedef unsigned int tkey;
 class Random {
     private:
         tkey rs1,rs2,rs3;
     public:
         tkey operator()() {
             rs1=(rs1<<)^(rs2>>)^rs3;
             rs2=(rs2<<)^(rs3>>)^rs1;
             rs3=(rs1<<)^(rs2>>)^rs2;
             return rs1^rs2^rs3;
         }
         void seed(tkey x) {
             rs1=x;
             rs2=rs1^0x64db3c5e;
             rs3=rs1^0xdb7a6f81;
         }
         Random() {
             seed(0x86e241ca);
         }
 } random;
 template<typename tp>
 class Treap {
     private:
         class TNode {
             private:
                 int p_size,p_csize;
             public:
                 tp val;int cnt;
                 tkey key;
                 TNode *lc,*rc;
                 TNode(tp v) {
                     val=v;p_size=;
                     p_csize=cnt=;
                     key=random();
                     lc=rc=;
                 }
                 inline int size()const{return this?this->p_size:;}
                 inline int csize()const{return this?this->p_csize:;}
                 void combine() {
                     p_size=+lc->size()+rc->size();
                     p_csize=cnt+lc->csize()+rc->csize();
                 }
                 void split(int k,TNode*& l,TNode*& r) {
                     if(!this) {
                         l=r=;return;
                     }
                     if(k<=lc->size()) {
                         lc->split(k,l,r);
                         lc=r;r=this;
                     } else {
                         rc->split(k-lc->size()-,l,r);
                         rc=l;l=this;
                     }
                     combine();
                 }
                 tp min() const {
                     const TNode *cur=this;
                     while(cur->lc) cur=cur->lc;
                     return cur->val;
                 }
                 tp max() const {
                     const TNode *cur=this;
                     while(cur->rc) cur=cur->rc;
                     return cur->val;
                 }
         } *root;
         TNode* merge(TNode* l,TNode* r) {
             if(!r) return l;
             if(!l) return r;
             if(l->key<r->key) {
                 l->rc=merge(l->rc,r);
                 l->combine();
                 return l;
             } else {
                 r->lc=merge(l,r->lc);
                 r->combine();
                 return r;
             }
         }
     public:
         Treap(){root=;}
         int size()const{return root->size();}
         int count()const{return root->csize();}
         int rank(tp v) const {
             int ans=;
             TNode *cur=root;
             while(cur) {
                 if(v<cur->val) cur=cur->lc;
                 else {
                     ans+=cur->lc->csize();
                     if(v>cur->val) ans+=cur->cnt,cur=cur->rc;
                     else return ans+;
                 }
             }
             return ans;
         }
         int nrank(tp v) const {
             int ans=;
             TNode *cur=root;
             while(cur) {
                 if(v<cur->val) cur=cur->lc;
                 else ans+=cur->lc->size()+,cur=cur->rc;
             }
             return ans;
         }
         void insert(tp v) {
             int k=nrank(v);
             TNode *l,*m,*r,*t;
             root->split(k,t,r);
             t->split(k-,l,m);
             if(m&&m->val==v) ++m->cnt,m->combine();
             else m=merge(m,new TNode(v));
             root=merge(merge(l,m),r);
         }
         void erase(tp v) {
             int k=nrank(v);
             TNode *l,*m,*r,*t;
             root->split(k,t,r);
             t->split(k-,l,m);
             if(!--m->cnt) {
                 delete []m;m=;
             } else m->combine();
             root=merge(merge(l,m),r);
         }
         tp get_kth(int k) const {
             TNode *cur=root;
             while(cur) {
                 if(k<=cur->lc->csize()) cur=cur->lc;
                 else {
                     k-=cur->lc->csize();
                     if(k<=cur->cnt) return cur->val;
                     k-=cur->cnt;cur=cur->rc;
                 }
             }
         }
         tp prev(tp v) {
             int k=nrank(v);
             TNode *l,*m,*r,*t;
             tp ans;
             root->split(k,t,r);
             t->split(k-,l,m);
             ans=m->val<v?m->val:l->max();
             root=merge(merge(l,m),r);
             return ans;
         }
         tp next(tp v) {
             int k=nrank(v);
             TNode *l,*r;
             tp ans;
             root->split(k,l,r);
             ans=r->min();
             root=merge(l,r);
             return ans;
         }
 };

[模板] FHQ Treap