bzoj2989&&4170数列——二进制分组+主席树

时间:2024-04-19 16:37:08

题意的转化挺巧妙的

bzoj2989&&4170数列——二进制分组+主席树

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=;bool fl=false;
while(!isdigit(ch=getchar()))(ch=='-')&&(fl=true);
for(x=numb;isdigit(ch=getchar());x=x*+numb);
(fl==true)&&(x=-x);
}
namespace Miracle{
const int N=+;
const int U=;
int n,q;
pair<int,int>a[N];
int b[N];
char ch[];
struct node{
int ls,rs;
int sum;
void clear(){
ls=rs=sum=;
}
}t[*];
int tot;
int sta[N],top;
int del[*],dc;
bool die[*];
int nc(){
int r=dc?del[dc--]:++tot;
die[r]=;
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=,r=;
for(reg k=;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+;
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+,r,p);
}
}
void remove(int x){
if(!x||die[x]) return;
remove(t[x].ls);remove(t[x].rs);
t[x].clear();
die[x]=;
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=;
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+,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()-;i>=;--i)
remove(rt[A][i]);
for(reg i=rt[B].size()-;i>=;--i)
remove(rt[B][i]);
// cout<<" guibing "<<endl;
merge(A,B); rt[A].clear();pos[A].clear();
for(reg i=;i<(int)mem[A].size();++i){
if(i==){
rt[A].push_back();pos[A].push_back(mem[A][i].fi);
upda(rt[A][],,-U,U,mem[A][i].se);
}else{
if(mem[A][i-].fi==mem[A][i].fi){
int tmp=rt[A][rt[A].size()-];
rt[A][rt[A].size()-]=;
upda(rt[A][rt[A].size()-],tmp,-U,U,mem[A][i].se);
}else{
rt[A].push_back();pos[A].push_back(mem[A][i].fi);
upda(rt[A][rt[A].size()-],rt[A][rt[A].size()-],-U,U,mem[A][i].se);
}
}
}
}
int calc(int x1,int y1,int x2,int y2){
int ret=;
//cout<<" seventy-five "<<t[75].sum<<endl;
for(reg i=;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<?:rt[id][k1];
k2=k2<?: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=;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+,a+n+,cmp);
for(reg i=;i<=n;++i){
//cout<<"("<<a[i].se<<","<<a[i].fi<<")"<<endl;
++cnt;
mem[cnt].push_back(a[i]);
rt[cnt].push_back();
pos[cnt].push_back(a[i].fi);
upda(rt[cnt][],,-U,U,a[i].se);
sta[++top]=cnt;
while(top>&&mem[sta[top]].size()==mem[sta[top-]].size()){
bing(sta[top-],sta[top]);
--top;
}
}
// cout<<cnt<<" "<<top<<endl;
int k;
while(q--){
scanf("%s",ch+);
rd(x);rd(k);
if(ch[]=='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();
pos[cnt].push_back(x+k);
upda(rt[cnt][],,-U,U,x-k);
sta[++top]=cnt;
while(top>&&mem[sta[top]].size()==mem[sta[top-]].size()){
bing(sta[top-],sta[top]);
--top;
}
b[x]=k;
/// cout<<" seventy-five "<<t[75].sum<<endl;
// cout<<cnt<<" "<<top<<endl;
}
}
return ;
} }
signed main(){
// freopen("data.in","r",stdin);
// freopen("my.out","w",stdout);
Miracle::main();
return ;
} /*
Author: *Miracle*
Date: 2019/2/24 9:42:39
*/