线段树0tps求调，全RE

#include<bits/stdc++.h>
using namespace std;
const int N=5e5+5,inf=1e9+5;
int n,m,a[N];
int op,ql,qr;
struct tree{
    int tl,tr,t,s,l,r;
#define tl(p) h[p].tl
#define tr(p) h[p].tr
#define t(p) h[p].t
#define s(p) h[p].s
#define l(p) h[p].l
#define r(p) h[p].r
} h[N<<2];
inline int read(){
    int x=0,f=1;char ch=getchar();
    for(;!isdigit(ch);ch=getchar()) if(ch=='-') f=-1;
    for(;isdigit(ch);ch=getchar()) x=(x<<3)+(x<<1)+ch-'0';
    return x*f;}
void build(int l,int r,int k){ l(k)=l,r(k)=r;
    if(l==r){s(k)=tl(k)=t(k)=tr(k)=a[r];return;}
    int mid=l+r>>1;
    build(l,mid,k<<1);
    build(mid+1,r,k<<1|1);
    s(k)=s(k<<1)+s(k<<1|1);
    t(k)=tr(k<<1)+tl(k<<1|1);
    t(k)=max(t(k),max(t(k<<1),t(k<<1|1)));
    tl(k)=max(tl(k<<1),s(k<<1)+tl(k<<1|1));
    tr(k)=max(tr(k<<1|1),s(k<<1|1)+tr(k<<1));}
tree query(int k,int x,int y){
    if(x<=l(k)&&r(k)<=y) {return h[k];}
    int mid=l(k)+r(k)>>1;
    if(y<=mid) return query(k<<1,x,y);
    return query(k<<1|1,x,y);
    tree res,a=query(k<<1,x,y),b=query(k<<1|1,x,y);
    res.tl=max(a.tl,a.s+b.tl);
    res.tr=max(b.tr,a.tr+b.s);
    res.t=max(max(a.t,b.t),a.tr+b.tl);
    return res;}
void change(int k,int x,int y){
    if(l(k)==r(k)){s(k)=tl(k)=t(k)=tr(k)=y;return;}
    int mid=l(k)+r(k)>>1;
    if(x<=mid)change(k<<1,x,y);
    else change(k<<1|1,x,y);
    s(k)=s(k<<1)+s(k<<1|1);
    t(k)=tr(k<<1)+tl(k<<1|1);
    t(k)=max(t(k),max(t(k<<1),t(k<<1|1)));
    tl(k)=max(tl(k<<1),s(k<<1)+tl(k<<1|1));
    tr(k)=max(tr(k<<1|1),s(k<<1|1)+tr(k<<1));}
int main(){ n=read(),m=read();
    for(int i=1;i<=n;i++) a[i]=read();
    build(1,1,n);
    while(m--){ op=read(),ql=read(),qr=read();
        if(op==1){if(ql>qr) swap(ql,qr);
            cout<<query(1,ql,qr).t<<endl;
        } else change(1,ql,qr);
    } return 0;
}

线段树0tps求调，全RE