BZOJ3217 : ALOEXT

替罪羊树套Trie，Trie合并用线段树合并，注意常数优化。

顺便AC800题纪念~~~

#include<cstdio>
#include<cmath>
#include<algorithm>
using namespace std;
const int N=200010,inf=19,M=32000010;
struct info{
  int v1,v2;
  info(){v1=v2=0;}
  info(int _v1,int _v2){v1=_v1,v2=_v2;}
}maxv;
inline info merge(info a,info b){
  if(b.v1>a.v1){
    a.v2=b.v2>a.v1?b.v2:a.v1;
    a.v1=b.v1;
  }else if(b.v1>a.v2)a.v2=b.v1;
  return a;
}
struct node{int l,r,v;node(){}node(int _l,int _r,int _v){l=_l,r=_r,v=_v;}}T[M];
int rub,getn[M];
const double A=0.8;
int size[N],real[N],ex[N],son[N][2],val[N],f[N],tot,root,id[N],cnt;
info mv[N];
int h[N],pool[N];
int ans,cntpool,cntone,one[N];
int n,q,x,y,i,Pow[20],Inv[20];char ch;
//Trie begin
inline void Max(int&a,int b){if(a<b)a=b;}
inline int Newtrienode(int l,int r,int v){
  int x=getn[rub--];
  T[x]=node(l,r,v);
  return x;
}
void Ins(int&x,int a,int c,int p){
  if(!x)x=Newtrienode(0,0,0);
  T[x].v+=p;
  if(~a)Ins(c&Pow[a]?T[x].r:T[x].l,a-1,c,p);
}
int Merge(int x,int y){
  if(!x&&!y)return 0;
  return Newtrienode(Merge(T[x].l,T[y].l),Merge(T[x].r,T[y].r),T[x].v+T[y].v);
}
inline int Ask(int x,int c){
  int t=1048575,a;
  for(a=inf;t>ans&&~a;a--)if(c&Pow[a]){
    if(T[T[x].l].v)x=T[x].l;else t&=Inv[a],x=T[x].r;
  }else{
    if(T[T[x].r].v)x=T[x].r;else t&=Inv[a],x=T[x].l;
  }
  return t;
}
inline void Ask(int c){
  int i;
  for(i=1;i<=cntone;i++)Max(ans,one[i]^c);
  for(i=1;i<=cntpool;i++)Max(ans,Ask(pool[i],c));
}
void deltree(int x){
  if(!x)return;
  deltree(T[x].l);deltree(T[x].r);
  getn[++rub]=x;
}
//Trie end
//Scapegoat begin
inline void up(int x){
  mv[x]=info(ex[x]?val[x]:0,0);
  if(son[x][0])mv[x]=merge(mv[x],mv[son[x][0]]);
  if(son[x][1])mv[x]=merge(mv[x],mv[son[x][1]]);
}
inline int newnode(int p,int fa){
  int x=++tot;
  f[x]=fa;size[x]=real[x]=ex[x]=1;son[x][0]=son[x][1]=0;
  val[x]=p;
  mv[x]=info(p,0);
  Ins(h[x]=0,inf,p,1);
  return x;
}
inline int Newnode(int x,int fa){
  f[x]=fa;size[x]=1;real[x]=ex[x];son[x][0]=son[x][1]=0;
  mv[x]=info(ex[x]?val[x]:0,0);
  h[x]=0;
  return x;
}
int ins(int x,int p,int b){
  size[x]++;real[x]++;mv[x]=merge(mv[x],info(p,0));
  Ins(h[x],inf,p,1);
  if(!son[x][b])return son[x][b]=newnode(p,x);else return ins(son[x][b],p,b);
}
void dfs(int x){
  if(son[x][0])dfs(son[x][0]);
  id[++cnt]=x;
  if(son[x][1])dfs(son[x][1]);
}
int build(int fa,int l,int r){
  int mid=(l+r)>>1,x=Newnode(id[mid],fa);
  if(l<mid)size[x]+=size[son[x][0]=build(x,l,mid-1)],real[x]+=real[son[x][0]];
  if(r>mid)size[x]+=size[son[x][1]=build(x,mid+1,r)],real[x]+=real[son[x][1]];
  h[x]=Merge(h[son[x][0]],h[son[x][1]]);
  if(ex[x])Ins(h[x],inf,val[x],1);
  up(x);
  return x;
}
inline int rebuild(int x){
  cnt=0;dfs(x);
  for(int i=1;i<=cnt;i++)deltree(h[id[i]]);
  return build(f[x],1,cnt);
}
inline int kth(int k,int p){
  int x=root,rank;
  while(1){
    size[x]++;real[x]++;mv[x]=merge(mv[x],info(p,0));Ins(h[x],inf,p,1);
    rank=real[son[x][0]]+1;
    if(k==rank&&ex[x])return x;
    if(k<rank)x=son[x][0];else k-=rank+ex[x]-1,x=son[x][1];
  }
}
inline void kthchange(int k,int p){
  int x=root,rank,del;
  while(1){
    rank=real[son[x][0]]+1;
    if(k==rank&&ex[x])break;
    if(k<rank)x=son[x][0];else k-=rank+ex[x]-1,x=son[x][1];
  }
  for(del=val[x],val[x]=p;x;x=f[x])Ins(h[x],inf,del,-1),Ins(h[x],inf,p,1),up(x);
}
inline void kthdel(int k){
  int x=root,rank,del;
  while(1){
    rank=real[son[x][0]]+1;
    if(k==rank&&ex[x])break;
    if(k<rank)x=son[x][0];else k-=rank+ex[x]-1,x=son[x][1];
  }
  for(del=val[x],ex[x]=0;x;x=f[x])real[x]--,Ins(h[x],inf,del,-1),up(x);
}
inline void kthins(int k,int p){
  if(!root){root=newnode(p,0);return;}
  int x;
  if(k==1)x=ins(root,p,0);
  else if(k>n)x=ins(root,p,1);
  else{
    x=kth(k,p);
    if(son[x][0])x=ins(son[x][0],p,1);else{
      son[x][0]=newnode(p,x);
      x=son[x][0];
    }
  }
  int z=x,deep=0;while(f[z])z=f[z],deep++;
  if(deep<log(tot)/log(1/A))return;
  while((double)size[son[x][0]]<A*size[x]&&(double)size[son[x][1]]<A*size[x])x=f[x];
  if(!x)return;
  if(x==root){root=rebuild(x);return;}
  int y=f[x],b=son[y][1]==x,now=rebuild(x);
  son[y][b]=now;
}
inline void ask(int x,int a,int b,int c,int d){
  if(!x)return;
  if(c<=a&&b<=d){maxv=merge(maxv,mv[x]);if(h[x])pool[++cntpool]=h[x];return;}
  int mid=a+real[son[x][0]];
  if(ex[x]&&c<=mid&&mid<=d)maxv=merge(maxv,info(val[x],0)),one[++cntone]=val[x];
  if(c<mid)ask(son[x][0],a,mid-1,c,d);
  if(d>=mid+ex[x])ask(son[x][1],mid+ex[x],b,c,d);
}
//Scapegoat end
inline void read(int&a){
  char ch;while(!(((ch=getchar())>='0')&&(ch<='9')));
  a=ch-'0';while(((ch=getchar())>='0')&&(ch<='9'))(a*=10)+=ch-'0';
}
int main(){
  for(Pow[0]=i=1;i<=inf;i++)Pow[i]=Pow[i-1]<<1;
  for(i=0;i<=inf;i++)Inv[i]=Pow[i]^1048575;
  for(i=1;i<M;i++)getn[++rub]=i;
  read(n);read(q);
  for(i=1;i<=n;i++)read(val[i]),id[i]=i,ex[i]=1;
  root=build(0,1,tot=n);
  while(q--){
    while(!(((ch=getchar())=='D')||(ch=='F')||(ch=='C')||(ch=='I')));
    read(x);
    if(ch!='D')read(y);
    if(ch=='F'){
      x=(x+ans)%n,y=(y+ans)%n;
      maxv=info();cntpool=cntone=0;
      ask(root,1,n,x+1,y+1);
      ans=0;
      Ask(maxv.v2);
      printf("%d\n",ans);
    }else if(ch=='C')x=(x+ans)%n,y=(y+ans)&1048575,kthchange(x+1,y);
    else if(ch=='I')x=(x+ans)%n,y=(y+ans)&1048575,kthins(x+1,y),n++;
    else x=(x+ans)%n,kthdel(x+1),n--;
  }
  return 0;
}