SBT模版

 /*Author:WNJXYK*/
 #include<cstdio>
 using namespace std;

 const int Maxn=;
 struct SBT{
     int left;
     int right;
     int size;
     int key;
 };
 SBT tree[Maxn+];
 int root,cnt;

 inline void rotate_l(int &x){
     int y=tree[x].right;
     tree[x].right=tree[y].left;
     tree[y].left=x;
     tree[y].size=tree[x].size;
     tree[x].size=+tree[tree[x].left].size+tree[tree[x].right].size;
     x=y;
 }

 inline void rotate_r(int &x){
     int y=tree[x].left;
     tree[x].left=tree[y].right;
     tree[y].right=x;
     tree[y].size=tree[x].size;
     tree[x].size=tree[tree[x].left].size++tree[tree[x].right].size;
     x=y;
 }

 void maintain(int &x,bool flag){
     //printf("MainTain %d\n",x);
     if (flag==false){
         if (tree[tree[tree[x].left].left].size>tree[tree[x].right].size){
             rotate_r(x);
         }
         else if (tree[tree[tree[x].left].right].size>tree[tree[x].right].size){
             rotate_l(tree[x].left);
             rotate_r(x);
         }else return ;
     }else{
         if (tree[tree[tree[x].right].right].size>tree[tree[x].left].size){
             rotate_l(x);
         }else if (tree[tree[tree[x].right].left].size>tree[tree[x].left].size){
             rotate_r(tree[x].right);
             rotate_l(x);
         }else return ;
     }
     maintain(tree[x].left,false);
     maintain(tree[x].right,true);
     maintain(x,true);
     maintain(x,false);
 }
 void insert(int &x,int sp){
     if (!x){
         x=++cnt;
         tree[x].left=tree[x].right=;
         tree[x].size=;
         tree[x].key=sp;
     }else{
         tree[x].size++;
         if (sp<tree[x].key){
             insert(tree[x].left,sp);
         }else{
             insert(tree[x].right,sp);
         }
         maintain(x,sp>=tree[x].key);
     }
 }

 int del(int &x,int sp){
     tree[x].size--;
     if (sp==tree[x].key || ( sp<tree[x].key && tree[x].left==) || (sp>tree[x].key && tree[x].right==)){
         int y=tree[x].key;
         if (tree[x].left== ||tree[x].right==){
             x=tree[x].left+tree[x].right;
             }else{
             tree[x].key=del(tree[x].left,tree[x].key+);
         }
         return y;
     }else{
         if (sp<tree[x].key){
             return del(tree[x].left,sp);
         }else{
             return del(tree[x].right,sp);
         }
     }
 }

 inline int getMax(){
     int i;
     for (i=root;tree[i].right;i=tree[i].right);
     return tree[i].key;
 }

 inline int getMin(){
     int i;
     for (i=root;tree[i].left;i=tree[i].left);
     return tree[i].key;
 }

 int rank(int &x,int sp){
     if (sp<tree[x].key){
         return rank(tree[x].left,sp);
     }else if (sp>tree[x].key){
         return rank(tree[x].right,sp)+tree[tree[x].left].size+;
     }
     return tree[tree[x].left].size+;
 }

 int select(int &x,int rak){
     int rk=tree[tree[x].left].size+;
     if (rak<rk){
         return select(tree[x].left,rak);
     }else if (rak>rk){
         return select(tree[x].right,rak-rk);
     }
     return tree[x].key;
 }

 int pred(int &x,int y,int sp){
     if (x==) return y;
     if (tree[x].key<sp){
         return pred(tree[x].right,x,sp);
     }
     return pred(tree[x].left,y,sp);
 }

 int succ(int &x,int y,int sp){
     if (x==) return y;
     if (tree[x].key>sp){
         return succ(tree[x].left,x,sp);
     }
     return succ(tree[x].right,y,sp);
 }

 inline void init(){
     root=cnt=;
 }

 int main(){
     init();
     return ;
 }