非旋转Treap——普通平衡树

扔板跑……

 #include<bits/stdc++.h>
 #define N 100010
 #define mp make_pair
 using namespace std;
 typedef pair<int,int> par;
 int n,x,rt;
 struct Treap_Without_rotate{
     int ls[N],rs[N],rnd[N],val[N],size[N],cnt;
     inline void pushup(int x){size[x]=size[ls[x]]+size[rs[x]]+;}
     par split(int k,int x){
         if(!x)return mp(,k);int l=ls[k],r=rs[k];
         if(x==size[l]){ls[k]=;pushup(k);return mp(l,k);}
         if(x==size[l]+){rs[k]=;pushup(k);return mp(k,r);}
         if(x<size[l]){
             par tmp=split(l,x);
             ls[k]=tmp.second;pushup(k);return mp(tmp.first,k);
         }
         par tmp=split(r,x-size[l]-);
         rs[k]=tmp.first;pushup(k);return mp(k,tmp.second);
     }
     int merge(int x,int y){
         if(x==||y==)return x+y;
         if(rnd[x]<rnd[y]){rs[x]=merge(rs[x],y);pushup(x);return x;}
         else{ls[y]=merge(x,ls[y]);pushup(y);return y;}
     }
     int queryrank(int x,int k){
         int ans=,tmp=(int)1e9;
         while(k){
             if(x==val[k])tmp=min(tmp,ans+size[ls[k]]+);
             if(x>val[k])ans+=size[ls[k]]+,k=rs[k];
             else k=ls[k];
         }
         return tmp==(int)1e9?ans:tmp;
     }
     int find(int x,int k){
         for(;;){
             if(size[ls[k]]==x-)return val[k];
             if(size[ls[k]]>x-)k=ls[k];
             else x=x-size[ls[k]]-,k=rs[k];
         }
     }
     int querypre(int x,int k){
         int ans=-(int)1e9;
         while(k){
             if(val[k]<x)ans=max(ans,val[k]),k=rs[k];
             else k=ls[k];
         }return ans;
     }
     int querysub(int x,int k){
         int ans=(int)1e9;
         while(k){
             if(val[k]>x)ans=min(ans,val[k]),k=ls[k];
             else k=rs[k];
         }return ans;
     }
     void ins(int x){
         int k=queryrank(x,rt);par tmp=split(rt,k);
         val[++cnt]=x;rnd[cnt]=rand();size[cnt]=;
         rt=merge(tmp.first,cnt);rt=merge(rt,tmp.second);
     }
     void del(int x){
         int k=queryrank(x,rt);par t1=split(rt,k),t2=split(t1.first,k-);
         rt=merge(t2.first,t1.second);
     }
 }T;
 inline int read(){
     int f=,x=;char ch;
     do{ch=getchar();if(ch=='-')f=-;}while(ch<''||ch>'');
     do{x=x*+ch-'';ch=getchar();}while(ch>=''&&ch<='');
     return f*x;
 }
 int main(){
     n=read();srand();
     for(int i=;i<=n;i++){
         int opt=read(),x=read();
         if(opt==)T.ins(x);
         if(opt==)T.del(x);
         if(opt==)printf("%d\n",T.queryrank(x,rt));
         if(opt==)printf("%d\n",T.find(x,rt));
         if(opt==)printf("%d\n",T.querypre(x,rt));
         if(opt==)printf("%d\n",T.querysub(x,rt));
     }
     return ;
 }