#define _CRT_SECURE_NO_WARNINGS
#include<cmath>
#include<iostream>
#include<stdio.h>
#include<algorithm>
#include<map>
#include<string.h>
using namespace std;
#define rep(i,t,n) for(int i =(t);i<=(n);++i)
#define per(i,n,t) for(int i =(n);i>=(t);--i)
#define mmm(a,b) memset(a,b,sizeof(a))
#define ls(n) node[n].ch[0]
#define rs(n) node[n].ch[1]
const int N = ;
const int INF = 0x3f3f3f3f; struct Splay {
struct Node {
int fa, ch[];
bool flip;
int v, add, maxn, s;
void init(int val)
{
v = maxn = val;
s = ;
add = flip = ch[] = ch[] = ;
}
}node[N];
int root;
//维护一个结点
void pushup(int n)
{
node[n].maxn = max(node[n].v, max(node[ls(n)].maxn, node[rs(n)].maxn));
node[n].s = node[ls(n)].s + node[rs(n)].s + ;
}
//标记向下传
void pushdown(int n)
{
if (n == ) return;
if (node[n].add) {
if (ls(n)) {
node[ls(n)].v += node[n].add;
node[ls(n)].maxn += node[n].add;
node[ls(n)].add += node[n].add;
}
if (rs(n)) {
node[rs(n)].v += node[n].add;
node[rs(n)].maxn += node[n].add;
node[rs(n)].add += node[n].add;
}
node[n].add = ;
}
if (node[n].flip) {
if (ls(n)) node[ls(n)].flip ^= ;
if (rs(n)) node[rs(n)].flip ^= ;
swap(ls(n), rs(n));
node[n].flip = ;
}
}
//旋转
void rotate(int n, int d)
{
int fn = node[n].fa;
int ffn = node[fn].fa;
node[fn].ch[d ^ ] = node[n].ch[d];
node[node[n].ch[d]].fa = fn; node[n].ch[d] = fn;
node[fn].fa = n; node[ffn].ch[rs(ffn) == fn] = n;
node[n].fa = ffn;
pushup(fn);
}
//将结点n转到goal下
void splay(int n, int goal)
{
while (node[n].fa != goal)
{
int fn = node[n].fa;
int ffn = node[fn].fa;
pushdown(ffn), pushdown(fn), pushdown(n);
bool d = (ls(fn) == n);
bool d1 = (ls(ffn) == fn);
if (ffn == goal) rotate(n, d);
else
{
if (d == d1) rotate(fn, d1); else rotate(n, d);
rotate(n, d1);
}
}
pushup(n);
if (goal == ) root = n;
}
//找寻中序遍历中的第pos个结点
int select(int pos)
{
int u = root;
pushdown(u);
while (node[ls(u)].s != pos)
{
if (pos < node[ls(u)].s) u = ls(u);
else
{
pos -= node[ls(u)].s + ;
u = rs(u);
}
pushdown(u);
}
return u;
}
//查询l~r最大值
int query(int l, int r)
{
int u = select(l - ), v = select(r + );
splay(u, ); splay(v, u);
return node[ls(v)].maxn;
}
//给l~r加上val
void update(int l, int r, int val)
{
int u = select(l - ), v = select(r + );
splay(u, ); splay(v, u);
node[ls(v)].v += val;
node[ls(v)].maxn += val;
node[ls(v)].add += val;
}
//翻转l~r
void reverse(int l, int r)
{
int u = select(l - ), v = select(r + );
splay(u, ); splay(v, u);
node[ls(v)].flip ^= ;
}
//类似二分来建树，就是这段代码现在的我还不会用指针来替换
int build(int l, int r)
{
if (l > r) return ;
if (l == r) return l;
int mid = (l + r) >> ;
int L, R;
ls(mid) = L = build(l, mid - );
rs(mid) = R = build(mid + , r);
node[L].fa = node[R].fa = mid;
pushup(mid);
return mid;
}
//初始化
void init(int n)
{
node[].init(-INF); node[].s = ;
node[].init(-INF);
node[n + ].init(-INF);
for (int i = ; i <= n + ; i++)
node[i].init();
root = build(, n + );
node[root].fa = node[].fa = ;
ls() = root;
}
}splay_tree; int main()
{
int n, m;
scanf("%d%d", &n, &m);
splay_tree.init(n);
for (int i = ; i < m; i++)
{
int opt, l, r, v;
scanf("%d%d%d", &opt, &l, &r);
if (opt == ) { scanf("%d", &v); splay_tree.update(l, r, v); }
if (opt == ) splay_tree.reverse(l, r);
if (opt == ) printf("%d\n", splay_tree.query(l, r));
}
return ;
}
/*
const int maxn = 55;
const int inf = 1e9 + 5;
ll n,m;
struct splay_tree {
struct node {
int val, mx, add, sz, son[2];
bool rev;
void init(int _val) { val = mx = _val, sz = 1, add = rev = son[0] = son[1]; }
}T[maxn];
int fa[maxn], root; void Rotate(int x, int kind) {
int y = fa[x], z = fa[y];
T[y].son[!kind] = T[x].son[kind], fa[T[x].son[kind]] = y;
T[x].son[kind] = y, fa[y] = x;
T[z].son[T[z].son[1] == y] = x, fa[x] = z;//orz
}
void Splay(int x,)
};
string s[maxn];
map<char, int> mmp; int main()
{
cin >> n >> m;
hehe.init();
for (int i = 0, a, b, c, d; i < m; i++) {
scanf("%d", &a);
if (a == 1) { scanf("%d%d%d", &b, &c, &d); hehe.update(b, c, d); }
else if (a == 2) { scanf("%d%d", &b, &c); hehe.Reverse(b, c); }
else { scanf("%d%d", &b, &c); printf("%d\n"); hehe.query(b, c); }
} return 0;
}*/