[模板] 线段树

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
const int amn=1e5+5;
int num[amn];
struct Segment_Tree{
    ll l,r,sum,lazy,len;
    #define ls rt<<1
    #define rs rt<<1|1
    #define trl(rt) tr[rt].l
    #define trr(rt) tr[rt].r
    #define trsum(rt) tr[rt].sum
    #define trlz(rt) tr[rt].lazy
    #define trlen(rt) tr[rt].len
    #define Mid int mid=(l+r)>>1
}tr[amn];
void push_up(int rt){
    trsum(rt)=trsum(ls)+trsum(rs);
}
void bulid(int rt,int l,int r){
    trl(rt)=l,trr(rt)=r;
    trlz(rt)=0;
    trlen(rt)=r-l+1;
    if(l==r){
        trsum(rt)=num[l];
    }
    Mid;
    build(ls,l,mid);
    build(rs,mid+1,r);
    push_up(rt);
}
void push_down(int rt,int l,int r){
    if(trlz(rt)){
        Mid;
        trsum(ls)=trlz(rt)*(mid-l+1);
        trsum(rs)=trlz(rt)*(r-mid);
        trlz(ls)=trlz(rs)=trlz(rt);
        trlz(rt)=0;
    }
    return ;
}
ll query(int rt,int l,int r,int L,int R){
    if(L<=l&&r<=R)return trsum(rt);
    Mid;
    push_down(rt);
    if(L<=mid)query(ls,l,mid,L,R);
    if(mid+1<=R)query(rs,mid+1,r,L,R);
}
void updata(int rt,int l,int r,int L,int R,int val){
    if(L<=l&&r<=R){
        trlz(rt)=val;
        trsum(rt)=trlz(rt)*trlen(rt);
        return ;
    }
    Mid;
    push_down(rt,l,r);
    if(L<=mid)updata(ls,l,mid,L,R,val);
    if(mid+1<=R)updata(rs,mid+1,r,L,R,val);
    push_up(rt);
}
int main(){
    
}