```cpp
#include<bits/stdc++.h>
#define int long long
#define lc (i<<1)
#define rc (i<<1|1)
#define mid (l+r>>1)
using namespace std;
struct node{
int maxs,rev,add;
}sgt[8000005];
int n,q,a[1000005];
void upd(node &x,node y,node z)
{
x.maxs=max(y.maxs,z.maxs);
}
void build(int i,int l,int r)
{
sgt[i].maxs=LLONG_MIN;
sgt[i].rev=LLONG_MIN;
if(l>=r)
{
sgt[i].maxs=a[r];
return;
}
build(lc,l,mid);
build(rc,mid+1,r);
upd(sgt[i],sgt[lc],sgt[rc]);
}
void pushdown_rev(int i)
{
int x=sgt[i].rev,y=sgt[i].add;
sgt[i].rev=LLONG_MIN;
sgt[i].add=0;
sgt[lc].rev=x;
sgt[lc].add+=y;
sgt[lc].maxs=x+y;
sgt[rc].rev=x;
sgt[rc].add+=y;
sgt[rc].maxs=x+y;
}
void pushdown_add(int i)
{
int x=sgt[i].add;
sgt[i].add=0;
sgt[lc].add+=x;
sgt[lc].maxs=max(sgt[lc].maxs,sgt[lc].maxs+x);
sgt[rc].add+=x;
sgt[rc].maxs=max(sgt[rc].maxs,sgt[rc].maxs+x);
}
void pushdown(int i)
{
if(sgt[i].rev!=LLONG_MIN) pushdown_rev(i);
else if(sgt[i].add) pushdown_add(i);
}
void mdf(int i,int l,int r,int x,int y,int d,int op)
{
if(x<=l&&r<=y)
{
if(op==1)
{
sgt[i].rev=d;
sgt[i].maxs=d;
}
else
{
sgt[i].add+=d;
sgt[i].maxs=max(sgt[i].maxs,sgt[i].maxs+d);
}
return;
}
pushdown(i);
if(x<=mid) mdf(lc,l,mid,x,y,d,op);
if(y>mid) mdf(rc,mid+1,r,x,y,d,op);
upd(sgt[i],sgt[lc],sgt[rc]);
}
int qry(int i,int l,int r,int x,int y)
{
//cerr<<"DEBUG: "<<l<<' '<<r<<' '<<x<<' '<<y<<' '<<sgt[i].maxs<<endl;
if(x<=l&&r<=y) return sgt[i].maxs;
int res=LLONG_MIN;
pushdown(i);
if(x<=mid) res=max(res,qry(lc,l,mid,x,y));
if(y>mid) res=max(res,qry(rc,mid+1,r,x,y));
return res;
}
void debug(int i=1,int l=1,int r=n)
{
cerr<<l<<'~'<<r<<": "<<sgt[i].maxs<<' '<<sgt[i].rev<<' '<<sgt[i].add<<endl;
if(l>=r) return;
debug(lc,l,mid);
debug(rc,mid+1,r);
}
signed main()
{
scanf("%lld%lld",&n,&q);
for(int i=1;i<=n;i++)
{
scanf("%lld",&a[i]);
}
build(1,1,n);
while(q--)
{
int op,x,y,z;
scanf("%lld%lld%lld",&op,&x,&y);
if(op>2) printf("%lld\n",qry(1,1,n,x,y));
else
{
scanf("%lld",&z);
mdf(1,1,n,x,y,z,op);
}
}
//debug();
return 0;
}
```
by Shiota_Kaede @ 2022-09-11 20:37:11
@[_JYqwq_](/user/400269) pushdown_rev挂了
by Azure__ @ 2022-09-11 20:42:48
@[_JYqwq_](/user/400269) 不开 ll 见祖宗。
by JackMerryYoung @ 2022-09-11 20:43:28
@[Azure__](/user/565945) 可以具体说一下哪儿挂了吗/kk
by Shiota_Kaede @ 2022-09-11 20:43:47
@[JackMerryYoung](/user/224558) 看看第二行是什么
by Shiota_Kaede @ 2022-09-11 20:44:03
@[_JYqwq_](/user/400269) 欧WSSB, 还有您写的好奇怪啊。
by JackMerryYoung @ 2022-09-11 20:44:52
lz写的真怪，我刚刚搞错了
by Azure__ @ 2022-09-11 20:46:18
```cpp
sgt[rc].add=sgt[lc].add=0;
sgt[rc].maxs=sgt[lc].maxs=x;
by Azure__ @ 2022-09-11 20:48:35
@[_JYqwq_](/user/400269)
by Azure__ @ 2022-09-11 20:48:49
@[Azure__](/user/565945) 改了后还是50pts..
by Shiota_Kaede @ 2022-09-11 20:52:01