【模板】关于线段树减小占用内存

//某题代码
#include<iostream>
#include<cstdio>
#include<map>
#include<cstring>
using namespace std;
long long a[100001],cnt=1;
long long Max(long long AA,long long BB){
    return AA>BB ? AA : BB;
}
struct node{
    int ls,rs,v;
}tree[10000001];
long long add(long long x,long long l,long long r,long long val){
    tree[x].v++;
    if(l==r) return 0;
    long long mid=(l+r)/2;
    if(val<=mid){
        if(tree[x].ls==0) tree[x].ls=++cnt;
        add(tree[x].ls,l,mid,val);
    }
    else{
        if(tree[x].rs==0) tree[x].rs=++cnt;
        add(tree[x].rs,mid+1,r,val);
    }
    return 0;
}
long long dlt(long long x,long long l,long long r,long long val){
    tree[x].v--;
    if(l==r) return 0;
    long long mid=(l+r)/2;
    if(val<=mid) dlt(tree[x].ls,l,mid,val);
    else dlt(tree[x].rs,mid+1,r,val);
    return 0;
} 
long long srch(long long x,long long l,long long r,long long val){
    if(l==r) return (long long)1;
    long long mid=(l+r)/2;
    if(mid>=val) return srch(tree[x].ls,l,mid,val);
    else return tree[tree[x].ls].v+srch(tree[x].rs,mid+1,r,val);
} 
inline long long read(){
    register long long s=(long long)0,w=(long long)1;
    register char ch=getchar();
    while(ch<'0'||ch>'9'){
        if(ch=='-') w=-1;
        ch=getchar();
    }
    while(ch>='0'&&ch<='9'){
        s=(s<<1)+(s<<3)+(ch^48);
        ch=getchar();
    }
    return s*w;
}
int main(){
    //freopen("sort.in","r",stdin);
    //freopen("sort.out","w",stdout);
    long long n,Q;
    n=read();
    Q=read();
    for(register long long i=1;i<=n;++i){
        a[i]=read();
        //N=Max(N,a[i]);
    }
    //N++;
    for(register long long i=1;i<=n;++i) add(1,1,N,a[i]*n+i-1);
    while(Q--){
        register long long op=0;
        op=read();
        if(op==1){
            register long long pos,shu;
            pos=read();
            shu=read();
            dlt(1,1,N,a[pos]*n+pos-1);
            add(1,1,N,shu*n+pos-1);
            a[pos]=shu;
        }
        else{
            register long long shu;
            shu=read();
            printf("%lld\n",srch(1,1,N,a[shu]*n+shu-1));
        }
    }
    return 0;
}

 map<long long,long long> tree

↑元素一多很容易爆内存