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P3919 【模板】可持久化线段树 1（可持久化数组）

#include
using namespace std;

#define lc tr[p].l
#define rc tr[p].r

const int N=1e6+5;
int n,m,idx;
int a[N],rot[N];
struct tree{
	int x,l,r;
}tr[N*24];

int build(int l,int r){
	int p=++idx;
	if(l==r){
		tr[p].x=a[l];
		return p;
	}
	int mid=l+r>>1;
	lc=build(l,mid);
	rc=build(mid+1,r);
	return p;
}

int change(int p,int l,int r,int x,int y){
	tr[++idx]=tr[p],p=idx;
	if(l==r){
		tr[p].x=y;
		return p;
	}
	int mid=l+r>>1;
	if(x>1;
	if(x>n>>m;
	for(int i=1;i>a[i];
	rot[0]=build(1,n);
	for(int i=1;i>v>>op>>x;
		if(op==1){
			cin>>y;
			rot[i]=change(rot[v],1,n,x,y);
		}
		else{
			cout

`#include
using namespace std;

#define lc tr[p].l
#define rc tr[p].r

const int N=1e6+5;
int n,m,idx;
int a[N],rot[N];
struct tree{
	int x,l,r;
}tr[N*24];

int build(int l,int r){
	int p=++idx;
	if(l==r){
		tr[p].x=a[l];
		return p;
	}
	int mid=l+r>>1;
	lc=build(l,mid);
	rc=build(mid+1,r);
	return p;
}

int change(int p,int l,int r,int x,int y){
	tr[++idx]=tr[p],p=idx;
	if(l==r){
		tr[p].x=y;
		return p;
	}
	int mid=l+r>>1;
	if(xchange(lc,l,mid,x,y);
	else rc=change(rc,mid+1,r,x,y);
	return p;
}

int check(int p,int l,int r,int x){
	if(l==r) return tr[p].x;
	int mid=l+r>>1;
	if(xreturn check(lc,l,mid,x);
	else return check(rc,mid+1,r,x);
}

signed main(){
	ios::sync_with_stdio(0);
	cin.tie(0),cout.tie(0);
	cin>>n>>m;
	for(int i=1;i>a[i];
	rot[0]=build(1,n);
	for(int i=1;i
		int v,op,x,y;
		cin>>v>>op>>x;
		if(op==1){
			cin>>y;
			rot[i]=change(rot[v],1,n,x,y);
		}
		else{
			coutcheck(rot[v],1,n,x)"\n";
			rot[i]=rot[v];
		}
	}
	return 0;
}`

P3834 【模板】可持久化线段树 2

#include
using namespace std;

#define N 200005
#define lc(x) tr[x].l
#define rc(x) tr[x].r
struct node{
	int l,r,s;
}tr[N*20];
int root[N],idx;
int n,m,a[N],b[N];

void insert(int x,int &y,int l,int r,int pos){
	y=++idx;
	tr[y]=tr[x]; tr[y].s++;
	if(l==r) return;
	int m=l+r>>1;
	if(pos>1;
	int s=tr[lc(y)].s-tr[lc(x)].s;
	if(k

`#include
using namespace std;

#define N 200005
#define lc(x) tr[x].l
#define rc(x) tr[x].r
struct node{
	int l,r,s;
}tr[N*20];
int root[N],idx;
int n,m,a[N],b[N];

void insert(int x,int &y,int l,int r,int pos){
	y=++idx;
	tr[y]=tr[x]; tr[y].s++;
	if(l==r) return;
	int m=l+r>>1;
	if(posinsert(lc(x),lc(y),l,m,pos);
	else insert(rc(x),rc(y),m+1,r,pos);
}
int query(int x,int y,int l,int r,int k){
	if(l==r) return l;
	int m=l+r>>1;
	int s=tr[lc(y)].s-tr[lc(x)].s;
	if(kreturn query(lc(x),lc(y),l,m,k);
	else return query(rc(x),rc(y),m+1,r,k-s);
}
int main(){
	scanf("%d%d",&n,&m);
	for(int i=1; i
		scanf("%d",&a[i]); b[i]=a[i];
	}
	sort(b+1,b+n+1);
	int bn=unique(b+1,b+n+1)-b-1;
	
	for(int i=1;i
		int id=lower_bound(b+1,b+bn+1,a[i])-b;
		insert(root[i-1],root[i],1,bn,id);
	}
	while(m--){
		int l,r,k; scanf("%d%d%d",&l,&r,&k);
		int id=query(root[l-1],root[r],1,bn,k);
		printf("%d\n",b[id]);
	}
	return 0;
}`