#pragma GCC optimize("O3", "unroll-loops") // "Ofast"
#pragma GCC target("avx2", "bmi", "bmi2", "lzcnt", "popcnt")
#include <bits/stdc++.h>
#define int long long
#define vt vector
#define pb push_back
#define all(x) (x).begin(), (x).end()
#define sz(x) (int)(x).size()
#define f first
#define s second
#define dbg(x) cerr << #x << " = " << x << '\n'
#define bit(x, i) ((x) >> (i) & 1)
using namespace std;
using ll = long long;
using ld = long double;
using pii = pair<int, int>;
const int N = 1e6 + 5, mod = 1e9 + 7;
const ll inf = 1e18 + 7;
const ld eps = 1e-6;
int n, q, a[N], d[N];
vt<array<int, 5>> qr;
struct Data {
int lst, frst, pref, suf, ans, len;
Data operator + (Data other) const {
Data res;
res.len = len + other.len, res.ans = max(ans, other.ans);
res.frst = frst, res.lst = other.lst;
res.pref = pref, res.suf = other.suf;
res.ans = max(ans, other.ans);
if (lst == other.frst) {
if (pref == len) res.pref += other.pref;
if (other.suf == other.len) res.suf += suf;
res.ans = max(res.ans, suf + other.pref);
}
return res;
}
}t[4 * N];
void build (int v = 1, int tl = 1, int tr = n + 1) {
if (tl == tr) {
t[v] = {d[tl], d[tl], 1, 1, 1, 1};
return;
}
int tm = tl + tr >> 1;
build(v << 1, tl, tm), build(v << 1 | 1, tm + 1, tr);
t[v] = t[v << 1] + t[v << 1 | 1];
}
void upd (int pos, int v = 1, int tl = 1, int tr = n + 1) {
if (tl == tr) {
t[v] = {d[tl], d[tl], 1, 1, 1, 1};
return;
}
int tm = tl + tr >> 1;
if (pos <= tm) upd(pos, v << 1, tl, tm);
else upd(pos, v << 1 | 1, tm + 1, tr);
t[v] = t[v << 1] + t[v << 1 | 1];
}
Data get (int l, int r, int v = 1, int tl = 1, int tr = n + 1) {
if (tl > r || tr < l) return {0, 0, 0, 0, 0, 0};
if (tl >= l && tr <= r) return t[v];
int tm = tl + tr >> 1;
return get(l, r, v << 1, tl, tm) + get(l, r, v << 1 | 1, tm + 1, tr);
}
void solve () {
cin >> n >> q;
for (int i = 1; i <= n; i++) cin >> a[i];
for (int i = 1; i < n; i++) d[i] = a[i + 1] - a[i];
bool sub1 = 1;
for (int i = 1; i <= q; i++) {
int tp, l, r, s = -1, c = -1;
cin >> tp >> l >> r;
if (tp < 3) cin >> s >> c;
qr.pb({tp, l, r, s, c});
sub1 &= (l == 1 && r == n);
}
if (sub1) {
int ans = 1, cur = 1, k = a[2] - a[1];
for (int i = 1; i < n; i++) {
if (a[i + 1] - a[i] == k) cur++;
else {
k = a[i + 1] - a[i];
ans = max(ans, cur);
cur = 2;
}
}
ans = max(ans, cur);
for (auto [tp, l, r, s, c]: qr) {
if (tp == 2) ans = n;
if (tp == 3) cout << ans << '\n';
}
return;
}
if (max(n, q) <= 1000) {
for (auto [tp, l, r, s, c]: qr) {
if (tp == 1) {
for (int i = l; i <= r; i++) a[i] += (s + (i - l) * c);
}
if (tp == 2) {
for (int i = l; i <= r; i++) a[i] = (s + (i - l) * c);
}
if (tp == 3) {
if (l == r) {
cout << "1\n";
continue;
}
int ans = 1, cur = 1, k = a[l + 1] - a[l];
for (int i = l; i < r; i++) {
if (a[i + 1] - a[i] == k) cur++;
else {
k = a[i + 1] - a[i];
ans = max(ans, cur);
cur = 2;
}
}
ans = max(ans, cur);
cout << ans << '\n';
}
}
return;
}
build();
for (auto [tp, l, r, s, c]: qr) {
if (tp < 3) {
if (tp == 1) a[l] += s;
if (tp == 2) a[l] = s;
if (l > 1) d[l - 1] = a[l] - a[l - 1], upd(l - 1);
if (l < n) d[l] = a[l + 1] - a[l], upd(l);
}
if (tp == 3) cout << get(l, r - 1).ans + 1 << '\n';
}
cout << '\n';
}
bool testcases = 0;
signed main() {
#ifdef ONLINE_JUDGE
freopen(".in", "r", stdin);
freopen(".out", "w", stdout);
#endif
cin.tie(0) -> sync_with_stdio(0);
int test = 1;
if (testcases) cin >> test;
for (int cs = 1; cs <= test; cs++) {
solve();
}
}
