#include<bits/stdc++.h>
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#define ll long long
using namespace std;
template<typename Lhs, typename Rhs> inline bool Max_self(Lhs &a, Rhs b) { if(b > a) { a = b; return true; } return false; }
template<typename Lhs, typename Rhs> inline bool Min_self(Lhs &a, Rhs b) { if(b < a) { a = b; return true; } return false; }
const ll N = 3e5 + 10;
const ll INF = 1e18;
struct que {
ll type = 0;
ll l = 0, r = 0;
ll s = 0, c = 0;
que() {};
friend istream& operator >> (istream& is, que& other) {
is >> other.type >> other.l >> other.r;
if(other.type <= 2) is >> other.s >> other.c;
return is;
}
};
ll n, q;
ll a[N];
que qq[N];
namespace sub1 {
bool check() {
for(ll i = 1; i <= q; ++ i) {
if(qq[i].l != 1 || qq[i].r != n) return false;
}
return true;
}
ll res = 1;
void solve() {
for(ll i = 1, j; i < n; i = j - 1) {
j = i + 1;
ll s = a[j] - a[i];
while(j <= n && a[j] - a[j - 1] == s) ++ j;
res = max(res, j - i);
}
for(ll i = 1; i <= q; ++ i) {
const auto& psy = qq[i];
if(psy.type == 3) cout << res << '\n';
else if(psy.type == 2) {
res = n;
}
}
}
}
namespace sub2 {
void solve() {
auto get_far = [&] (ll l, ll r) -> ll {
ll res = 1;
for(ll i = l, j; i < r; i = j - 1) {
j = i + 1;
ll s = a[j] - a[i];
while(j <= r && a[j] - a[j - 1] == s) ++ j;
res = max(res, j - i);
}
return res;
};
for(ll i = 1; i <= q; ++ i) {
const auto& psy = qq[i];
ll type = psy.type;
if(type == 1) {
ll add[2] = {psy.s, psy.c};
for(ll i = psy.l; i <= psy.r; ++ i) {
a[i] += add[0];
add[0] += add[1];
}
}
else if(type == 2) {
ll add[2] = {psy.s, psy.c};
for(ll i = psy.l; i <= psy.r; ++ i) {
a[i] = add[0];
add[0] += add[1];
}
}
else {
// cout << psy.l << ' ' << psy.r << '\n';
cout << get_far(psy.l, psy.r) << '\n';
}
}
}
}
namespace sub3 {
bool check() {
for(ll i = 1; i <= q; ++ i) {
if(qq[i].type < 3) return false;
}
return true;
}
struct Node {
struct state {
ll val = 0, len = 0;
state() {};
state(ll _val, ll _len) { val = _val; len = _len; };
};
state pref = state(), suf = state();
state sub = state();
ll len = 0;
Node() {};
Node(ll _val, ll _len) {
pref = state(_val, _len);
suf = state(_val, _len);
sub = state(0, 0);
len = _len;
}
Node operator + (const Node& other) const {
Node res;
res.pref = this -> pref;
if(this -> len == this -> pref.len && this -> pref.val == other.pref.val) {
res.pref.len += other.pref.len;
}
res.suf = other.suf;
if(other.len == other.suf.len && this -> suf.val == other.suf.val) {
res.suf.len += this -> suf.len;
}
if(Max_self(res.sub.len, this -> sub.len)) res.sub = this -> sub;
if(Max_self(res.sub.len, other.sub.len)) res.sub = other.sub;
int len_pref = min(this -> len - 1, this -> suf.len);
if(Max_self(res.sub.len, len_pref)) res.sub.val = this -> suf.val;
int len_suf = min(other.len - 1, other.pref.len);
if(Max_self(res.sub.len, len_suf)) res.sub.val = other.pref.val;
if(this -> suf.val == other.pref.val && Max_self(res.sub.len, len_pref + len_suf)) {
res.sub.val = this -> suf.val;
}
res.len = this -> len + other.len;
return res;
}
};
Node tree[N << 2];
ll diff[N];
void make_first(ll node, ll l, ll r, ll* value) {
if(l == r) {
tree[node] = Node(value[l], 1);
return;
}
ll mid = (l + r) >> 1;
make_first(node << 1, l, mid, value);
make_first(node << 1 | 1, mid + 1, r, value);
tree[node] = tree[node << 1] + tree[node << 1 | 1];
}
Node query(ll node, ll l, ll r, ll L, ll R) {
if(l > r || L > R || l > R || L > r) return Node(- INF, 0);
if(L <= l && r <= R) return tree[node];
ll mid = (l + r) >> 1;
return query(node << 1, l, mid, L, R) + query(node << 1 | 1, mid + 1, r, L, R);
}
void solve() {
for(ll i = 1; i <= n; ++ i) diff[i] = a[i] - a[i - 1];
make_first(1, 1, n, diff);
for(ll i = 1; i <= q; ++ i) {
const auto& psy = qq[i];
ll res = 0;
Node tmp = query(1, 1, n, psy.l, psy.r);
Max_self(res, tmp.pref.len);
// cout << res << '\n';
Max_self(res, tmp.sub.len + 1);
// cout << res << '\n';
Max_self(res, tmp.suf.len + 1);
// cout << res << '\n';
Min_self(res, psy.r - psy.l + 1);
cout << res << '\n';
}
}
}
int32_t main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
if (fopen("Progression.inp", "r")) {
freopen("Progression.inp", "r", stdin);
freopen("Progression.out", "w", stdout);
}
cin >> n >> q;
for(ll i = 1; i <= n; ++ i) cin >> a[i];
for(ll i = 1; i <= q; ++ i) cin >> qq[i];
if(sub1::check()) {
sub1::solve();
return 0;
}
if(sub3::check()) {
sub3::solve();
return 0;
}
sub2::solve();
return 0;
}
/// Code by vuavisao
