「SCOI2014」方伯伯的 OJ
和列队有点像，平衡树点分裂维护即可
但是需要额外用个set之类的对编号查找点的位置
插入完了后记得splay，删除时注意特判好多东西
Code:
#include <cstdio>
#include <cctype>
#include <set>
const int N=2e5+10;
template <class T>
void inline read(T &x)
{x=0;char c=getchar();while(!isdigit(c)) c=getchar();while(isdigit(c)) x=x*10+c-'0',c=getchar();
}
#define ls ch[now][0]
#define rs ch[now][1]
#define fa par[now]
int siz[N],ch[N][2],L[N],R[N],par[N],tot,root;
void connect(int f,int now,int typ){ch[fa=f][typ]=now;}
int identity(int now){return ch[fa][1]==now;}
void updata(int now){siz[now]=siz[ls]+siz[rs]+R[now]+1-L[now];}
void Rotate(int now)
{int p=fa,typ=identity(now);connect(p,ch[now][typ^1],typ);connect(par[p],now,identity(p));connect(now,p,typ^1);updata(p),updata(now);
}
void splay(int now,int to)
{to=par[to];if(!to) root=now;for(;fa!=to;Rotate(now))if(par[fa]!=to)Rotate(identity(now)^identity(fa)?now:fa);
}
struct yuucute
{int x,id;yuucute(){}yuucute(int X,int Id){x=X,id=Id;}bool friend operator <(yuucute a,yuucute b){return a.x<b.x;}bool friend operator ==(yuucute a,yuucute b){return a.x==b.x;}
};
std::set <yuucute> s;
std::set <yuucute>::iterator it;
#define yuulovely 1
int New(int l,int r)
{siz[++tot]=r+1-l,L[tot]=l,R[tot]=r;return tot;
}
int getnum(int x)
{it=--s.upper_bound(yuucute(x,yuulovely));return it->id;
}
void split(int now,int x)
{if(L[now]==R[now]) return;s.erase(yuucute(L[now],yuulovely));s.insert(yuucute(x,now));int lson=ls,rson=rs;if(L[now]<x){int lp=New(L[now],x-1);s.insert(yuucute(L[now],lp));connect(now,lp,0);connect(lp,lson,0);updata(lp);}if(x<R[now]){int rp=New(x+1,R[now]);s.insert(yuucute(x+1,rp));connect(now,rp,1);connect(rp,rson,1);updata(rp);}L[now]=R[now]=x;
}
void insl(int now,int ins)
{++siz[now];if(ls) insl(ls,ins);else connect(now,ins,0);
}
void insr(int now,int ins)
{++siz[now];if(rs) insr(rs,ins);else connect(now,ins,1);
}
int getlef(int now)
{if(ls) return getlef(ls);return now;
}
void erase(int now)
{if(!rs) {par[root=ls]=0,ls=0,updata(now);return;}splay(root=getlef(rs),rs);connect(root,ls,0);updata(root),par[root]=0;ls=rs=0,updata(now);
}
int getrank(int now,int &x)
{if(siz[ls]>=x) return getrank(ls,x);x-=siz[ls];if(x<=R[now]-L[now]+1) return now;x-=R[now]-L[now]+1;return getrank(rs,x);
}
int main()
{freopen("data.in","r",stdin);freopen("data.out","w",stdout);int n,m;read(n),read(m);root=New(1,n);s.insert(yuucute(1,root));int op,x,y,las=0;for(int i=1;i<=m;i++){read(op),read(x);x-=las;if(op==1){read(y),y-=las;int now=getnum(x);splay(now,root);printf("%d\n",las=siz[ls]+x+1-L[now]);split(now,x);L[now]=R[now]=y;s.erase(yuucute(x,yuulovely));s.insert(yuucute(y,now));}else if(op==2){int now=getnum(x);splay(now,root);printf("%d\n",las=siz[ls]+x+1-L[now]);split(now,x);erase(now);insl(root,now);splay(now,root);}else if(op==3){int now=getnum(x);splay(now,root);printf("%d\n",las=siz[ls]+x+1-L[now]);split(now,x);erase(now);insr(root,now);splay(now,root);}else{int now=getrank(root,x);printf("%d\n",las=x+L[now]-1);splay(now,root);}}return 0;
}2019.2.23
)
