rt,代码如下：

#include<bits/stdc++.h>
using namespace std;
const int maxn = 3e6+114;
const int inf = 1e9;
int tot,root;
struct Node{
	int val,sz,ls,rs,tag1,tag2,mx;//翻转标记和加法标记 
	int data;//这个节点存储的数据 
}treap[maxn];
int clone(int data){
	int New=++tot;
	treap[New].data=data;
	treap[New].val=rand();
	treap[New].sz=1;
	treap[New].tag1=0;
	treap[New].tag2=0;
	treap[New].mx=data;
	treap[New].ls=0;
	treap[New].rs=0;
	return New;
}
inline void pushup(int cur){
	if(cur==0) return ;
	treap[cur].sz=treap[treap[cur].ls].sz+treap[treap[cur].rs].sz+1;
	treap[cur].mx=max((treap[cur].ls==0?-inf:treap[treap[cur].ls].mx),max((treap[cur].rs==0?-inf:treap[treap[cur].rs].mx),treap[cur].data));
}
inline void rot(int cur){
	if(cur==0) return ;
	treap[cur].tag1^=1;
}
inline void add(int cur,int v){
	if(cur==0) return ;
	treap[cur].tag2+=v;
}
inline void pushdown(int cur){
	if(cur==0) return ;
	treap[cur].data+=treap[cur].tag2;
	treap[cur].mx+=treap[cur].tag2;
	if(treap[cur].ls!=0) treap[treap[cur].ls].tag2+=treap[cur].tag2;
	if(treap[cur].rs!=0) treap[treap[cur].rs].tag2+=treap[cur].tag2;
	treap[cur].tag2=0;
	if(treap[cur].tag1==1){
		swap(treap[cur].ls,treap[cur].rs);
		if(treap[cur].ls!=0) treap[treap[cur].ls].tag1^=1;
		if(treap[cur].rs!=0) treap[treap[cur].rs].tag1^=1;
		treap[cur].tag1=0;
	}
}
int merge(int x,int y){
	pushdown(x);
	pushdown(y);
    if (!x||!y) return x+y;
    if (treap[x].val<treap[y].val)
    {
        treap[x].rs=merge(treap[x].rs,y);
        pushup(x);
        return x;
    }
    else
    {
        treap[y].ls=merge(x,treap[y].ls);
        pushup(y);
        return y;
    }
}
void split(int cur,int x,int &l,int &r) {
	pushdown(cur);
	if(cur==0){
		l=r=0;
		return ;
	}
	if(treap[treap[cur].ls].sz>=x){
		r=cur;
		split(treap[cur].ls,x,l,treap[cur].ls);
	}
	else{
		l=cur;
		split(treap[cur].rs,x-treap[treap[cur].ls].sz-1,treap[cur].rs,r);
	}
	pushup(cur);
}
int n,T;
int main(){
	ios::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
    srand(time(0));
	cin>>n>>T;
	for(int i=1;i<=n;i++){
		root=merge(root,clone(0));
	}
	while(T--){
		int opt;
		cin>>opt;
		if(opt==1){
			int l,r,v;
			cin>>l>>r>>v;
			int x=0,y=0,z=0;
			split(root,l-1,x,z);
			split(z,r-l+1,y,z);
			add(y,v);
			root=merge(x,merge(y,z));
		}
		else if(opt==2){
			int l,r;
			cin>>l>>r;
			int x=0,y=0,z=0;
			split(root,l-1,x,z);
			split(z,r-l+1,y,z);
			rot(y);
			root=merge(x,merge(y,z));
		}
		else{
			int l,r;
			cin>>l>>r;
			int x=0,y=0,z=0;
			split(root,l-1,x,z);
			split(z,r-l+1,y,z);
			pushdown(y); 
			cout<<treap[y].mx<<'\n';
			root=merge(x,merge(y,z));
		}
	}
}