bzoj2989&&4170数列——二进制分组+主席树
题意的转化挺巧妙的
可以联想到曼哈顿距离!
并且,所谓的修改还要查询历史版本,并且修改之间不动只算一次,不就是给平面上加一个点吗?
看成(x,a[x])的点
就是一个菱形区域
转切比雪夫距离,变成矩形区域
所以
平面单点加,矩形查询和
1.cdq分治
2.树套树(离散化都不用)
3.二进制分组+主席树
这里,大炮打蚊子,用二进制分组来写
加入的点按操作二进制分组,每个组用主席树维护这个平面,查询在logn上查询,合并暴力重构,256MB又没有删除,所以重构完了把原来的树垃圾回收
注意:
主席树垃圾回收,从最后一个根开始,一个点不能删除两次,所以共用点打die标记,之后搜到返回即可。
代码:
写得很丑
其实不用vector,可以开数组,记录每个组的范围。每次sort,然后建树。
#include<bits/stdc++.h> #define reg register int #define il inline #define numb (ch^'0') #define mid ((l+r)>>1) #define fi first #define se second #define mp(a,b) make_pair(a,b) using namespace std; typedef long long ll; il void rd(int &x){ char ch;x=0;bool fl=false; while(!isdigit(ch=getchar()))(ch=='-')&&(fl=true); for(x=numb;isdigit(ch=getchar());x=x*10+numb); (fl==true)&&(x=-x); } namespace Miracle{ const int N=160000+5; const int U=160000; int n,q; pair<int,int>a[N]; int b[N]; char ch[233]; struct node{ int ls,rs; int sum; void clear(){ ls=rs=sum=0; } }t[40000*200]; int tot; int sta[N],top; int del[40000*200],dc; bool die[40000*200]; int nc(){ int r=dc?del[dc--]:++tot; die[r]=0; t[r].clear(); // cout<<" r "<<r<<" "<<t[r].sum<<" "<<t[r].ls<<" "<<t[r].rs<<endl; return r; //return ++tot; } int cnt; vector<pair<int,int> >mem[N]; vector<int>rt[N],pos[N]; bool cmp(pair<int,int>a,pair<int,int> b){//a<b? if(a.fi==b.fi) return a.se<b.se; return a.fi<b.fi; } void merge(int i,int j){ vector<pair<int,int> >tmp; int l=0,r=0; for(reg k=1;k<=(int)mem[i].size()+(int)mem[j].size();++k){ if(l>=(int)mem[i].size()){ tmp.push_back(mem[j][r++]); }else if(r>=(int)mem[j].size()){ tmp.push_back(mem[i][l++]); }else if(cmp(mem[i][l],mem[j][r])){ tmp.push_back(mem[i][l++]); }else{ tmp.push_back(mem[j][r++]); } } mem[i]=tmp; } void upda(int &x,int y,int l,int r,int p){ if(!x) x=nc(); t[x].sum=t[y].sum+1; if(l==r){return;} if(p<=mid){ t[x].rs=t[y].rs;upda(t[x].ls,t[y].ls,l,mid,p); }else{ t[x].ls=t[y].ls;upda(t[x].rs,t[y].rs,mid+1,r,p); } } void remove(int x){ if(!x||die[x]) return; remove(t[x].ls);remove(t[x].rs); t[x].clear(); die[x]=1; del[++dc]=x; } int query(int x,int y,int l,int r,int L,int R){ //cout<<" query "<<x<<" "<<y<<" "<<l<<" "<<r<<" goal "<<L<<" "<<R<<endl; //cout<<" sum "<<t[x].sum<<" and "<<t[y].sum<<endl; if(L<=l&&r<=R){ return t[x].sum-t[y].sum; } int ret=0; if(L<=mid) ret+=query(t[x].ls,t[y].ls,l,mid,L,R); if(mid<R) ret+=query(t[x].rs,t[y].rs,mid+1,r,L,R); return ret; } void bing(int A,int B){ //cout<<" merge "<<A<<" "<<B<<endl; // cout<<mem[A].size()<<" and "<<mem[B].size()<<endl; for(reg i=rt[A].size()-1;i>=0;--i) remove(rt[A][i]); for(reg i=rt[B].size()-1;i>=0;--i) remove(rt[B][i]); // cout<<" guibing "<<endl; merge(A,B); rt[A].clear();pos[A].clear(); for(reg i=0;i<(int)mem[A].size();++i){ if(i==0){ rt[A].push_back(0);pos[A].push_back(mem[A][i].fi); upda(rt[A][0],0,-U,U,mem[A][i].se); }else{ if(mem[A][i-1].fi==mem[A][i].fi){ int tmp=rt[A][rt[A].size()-1]; rt[A][rt[A].size()-1]=0; upda(rt[A][rt[A].size()-1],tmp,-U,U,mem[A][i].se); }else{ rt[A].push_back(0);pos[A].push_back(mem[A][i].fi); upda(rt[A][rt[A].size()-1],rt[A][rt[A].size()-2],-U,U,mem[A][i].se); } } } } int calc(int x1,int y1,int x2,int y2){ int ret=0; //cout<<" seventy-five "<<t[75].sum<<endl; for(reg i=1;i<=top;++i){ int id=sta[i]; // cout<<" id "<<id<<" mem "<<mem[id].size()<<" pos "<<pos[id].size()<<endl; // cout<<" seventy-five "<<t[75].sum<<endl; int k1=lower_bound(pos[id].begin(),pos[id].end(),y1)-pos[id].begin(); --k1; int k2=upper_bound(pos[id].begin(),pos[id].end(),y2)-pos[id].begin(); --k2; // cout<<k1<<" and "<<k2<<endl; // cout<<" seventy-five "<<t[75].sum<<endl; k1=k1<0?0:rt[id][k1]; k2=k2<0?0:rt[id][k2]; ret+=query(k2,k1,-U,U,x1,x2); // cout<<" seventy-five "<<t[75].sum<<endl; } return ret; } int main(){ rd(n);rd(q); int x; for(reg i=1;i<=n;++i){ rd(x);a[i]=mp(i+x,i-x); b[i]=x; } // cout<<cmp(mp(3,-1),mp(6,-2))<<endl; sort(a+1,a+n+1,cmp); for(reg i=1;i<=n;++i){ //cout<<"("<<a[i].se<<","<<a[i].fi<<")"<<endl; ++cnt; mem[cnt].push_back(a[i]); rt[cnt].push_back(0); pos[cnt].push_back(a[i].fi); upda(rt[cnt][0],0,-U,U,a[i].se); sta[++top]=cnt; while(top>1&&mem[sta[top]].size()==mem[sta[top-1]].size()){ bing(sta[top-1],sta[top]); --top; } } // cout<<cnt<<" "<<top<<endl; int k; while(q--){ scanf("%s",ch+1); rd(x);rd(k); if(ch[1]=='Q'){ // cout<<" seventy-five "<<t[75].sum<<endl; printf("%d\n",calc(x-b[x]-k,x+b[x]-k,x-b[x]+k,x+b[x]+k)); // cout<<" seventy-five "<<t[75].sum<<endl; }else{ ++cnt; mem[cnt].push_back(mp(x+k,x-k)); rt[cnt].push_back(0); pos[cnt].push_back(x+k); upda(rt[cnt][0],0,-U,U,x-k); sta[++top]=cnt; while(top>1&&mem[sta[top]].size()==mem[sta[top-1]].size()){ bing(sta[top-1],sta[top]); --top; } b[x]=k; /// cout<<" seventy-five "<<t[75].sum<<endl; // cout<<cnt<<" "<<top<<endl; } } return 0; } } signed main(){ // freopen("data.in","r",stdin); // freopen("my.out","w",stdout); Miracle::main(); return 0; } /* Author: *Miracle* Date: 2019/2/24 9:42:39 */