bzoj 3224: Tyvj 1728 普通平衡树

#include<iostream>
#include<cstdio>
#include<cmath>
#include<cstring>
#include<algorithm>
#include<cstdlib>
#include<queue>
#include<vector>
#define fo(i,a,b) for(int i=a;i<=b;i++)
#define fod(i,a,b) for(int i=a;i>=b;i--)
using namespace std;
const int N=1e5+10,INF=1<<30;
struct Node
{
int v,sz;
Node *fa,*ch[2];
Node(int v=0):v(v){sz=1;ch[0]=ch[1]=fa=NULL;}
int cmp(int x) {return x==v?-1:x>v;}
void up() {
sz=1;
if(ch[0]!=NULL) sz+=ch[0]->sz;
if(ch[1]!=NULL) sz+=ch[1]->sz;
}
}*pool[N*2];
int top=0,n;
void init() {for(int i=0;i<N;i++) pool[i]=new Node();}
void newnode(Node* &p,int v,Node *fa){p=pool[top++]; *p=Node(v); p->fa=fa;}
void del(Node* &p) {pool[--top]=p;p=NULL;}
struct SplayTree{
Node *root;
inline int pd(Node *p){return p->fa->ch[1]==p;}
inline void rotate(Node* p)
{
int c=pd(p)^1;Node *t=p->fa;
t->ch[c^1]=p->ch[c];
if(p->ch[c])p->ch[c]->fa=t;
if((p->fa=t->fa)!=NULL) p->fa->ch[p->fa->ch[1]==t]=p;
t->fa=p;p->ch[c]=t;t->up();p->up();
if(p->fa==NULL) root=p;
}
inline void splay(Node* p,Node *FA)
{
for(;p->fa!=FA;rotate(p))
if(p->fa->fa!=FA) rotate(pd(p)==pd(p->fa)?p->fa:p);
}
void insert(Node* p,int val)
{
if(root==NULL){newnode(root,val,NULL);return ;}
Node *fa=NULL;
while(p!=NULL) fa=p,p=p->ch[val > p->v];
newnode(p,val,fa);fa->ch[val>fa->v]=p;
for(fa=p->fa;fa!=NULL;fa=fa->fa)
fa->up();
splay(p,NULL);
}
inline Node* find(Node *p,int val)
{
while(p!=NULL) {
int tcmp=p->cmp(val);
if(tcmp==-1) return p;
p=p->ch[tcmp];
}
return NULL;
}
Node* MAX(Node* p){
if(p==NULL) return NULL;
while(p->ch[1]!=NULL) p=p->ch[1];
return p;
}
Node* merge(Node* a,Node* b)
{
if(!b) return a;
if(!a) return b;
Node *t=MAX(a);
splay(t,NULL);
t->ch[1]=b;b->fa=t;t->up();
return t;
}
void remove(Node* p,int val)
{
Node* pos=find(root,val);
splay(pos,NULL);
pos=root;del(root);
root=merge(pos->ch[0],pos->ch[1]);
if(root!=NULL)root->fa=NULL;
}
inline int rank(Node* p,int val)
{
int ret=1;
while(p!=NULL){
int tcmp=val > p->v,d=p->ch[0]?p->ch[0]->sz:0;
if(tcmp) ret+=d+1; p=p->ch[tcmp];
}
return ret;
}
inline int kth(Node* p,int k)
{
while(p!=NULL){
int d=p->ch[0]?p->ch[0]->sz:0;
if(k==d+1) return p->v;
if(k<d+1) p=p->ch[0];
else k-=d+1,p=p->ch[1];
}
return -1;
}
inline int Pre(Node* p,int val)
{
int ret=-INF;
while(p!=NULL){
int tcmp=val > p->v;
if(tcmp) ret=max(ret,p->v);
p=p->ch[tcmp];
}
return ret;
}
inline int Sub(Node* p,int val)
{
int ret=INF;
while(p!=NULL){
int tcmp=val < p->v;
if(tcmp) ret=min(ret,p->v);
p=p->ch[tcmp^1];
}
return ret;
}
inline void insert(int x){insert(root,x);}
inline void remove(int x){remove(root,x);}
inline int rank(int x){return rank(root,x);}
inline int kth(int x){return kth(root,x);}
inline int Pre(int x){return Pre(root,x);}
inline int Sub(int x){return Sub(root,x);}
}splay;
int main()
{
int op,x;
scanf("%d",&n);
init();
while(n--) {
scanf("%d%d",&op,&x);
if(op==1) splay.insert(x);
else if(op==2) splay.remove(x);
else if(op==3) printf("%d\n",splay.rank(x));
else if(op==4) printf("%d\n",splay.kth(x));
else if(op==5) printf("%d\n",splay.Pre(x));
else printf("%d\n",splay.Sub(x));
}
return 0;
}