#include <vector>
#include<iostream>
#include <algorithm>
#include <cmath>
#include <iomanip>
#include <fstream>
#include <string>
#include <set>
#include <deque>
#include <queue>
#include <map>
#include <bitset>
#include <random>
#include <cassert>
#include <unordered_map>
#include <unordered_set>
#include<math.h>
using namespace std;
typedef unsigned int ui;
typedef long long             ll;
typedef unsigned long long     ull;
typedef long double            ld;
#define endl              "\n"
#define all(a)            a.begin(), a.end()
#define allr(a)           a.rbegin(), a.rend()
#define pb                push_back
#define pikachu           push_back
#define F                 first
#define S                 second
const ll MAXN = 1e5+1;
struct segtree {
    ll ind;
    ll cnt[8];
};
segtree add[MAXN];
segtree t[4 * MAXN];
ll a[MAXN];
ll n;

void build(ll v, ll tl, ll tr) {
    if (tl == tr) {
        t[v].cnt[a[tl]]++;
        t[v].ind = a[tl];
    }
    else {
        ll tm = (tl + tr) / 2;
        build(v * 2, tl, tm);
        build(v * 2 + 1, tm + 1, tr);
        for (int i = 0; i <= 7; i++) {
            t[v].cnt[i] = t[v * 2].cnt[i] + t[v * 2 + 1].cnt[i];
        }
    }
}

void update(ll v, ll tl, ll tr, ll l, ll r, ll color) {
    if (l > r)
        return;
    if (l == tl && tr == r) {
        for (ll i = 0; i <= 8; i++) {
            if (t[v].cnt[i]) {
                t[v].cnt[i]--;
                t[v].cnt[i ^ color]++;
            }
        }
    }
    else {
        ll tm = (tl + tr) / 2;
        update(v * 2, tl, tm, l, min(r, tm), color);
        update(v * 2 + 1, tm + 1, tr, max(l, tm + 1), r, color);
        for (int i = 0; i <= 8; i++) {
            t[v].cnt[i] = t[2 * v].cnt[i] + t[2 * v + 1].cnt[i];
        }
    }
}
ll quee(ll v, ll vl, ll vr, ll l, ll r,ll x) {
    if (r < vl || vr < l)
        return 0;
    if (l <= vl && vr <= r)
        return t[v].cnt[x];
    ll vm = vl + (vr - vl) / 2;
    ll  ql = quee(2 * v, vl, vm, l, r, x);
    ll  qr = quee(2 * v + 1, vm + 1, vr, l, r, x);
    return ql + qr;
}
ll ask(ll l, ll r, ll x) {
    ll no = 1e9+9;
    if (r == no || l == no) {
        return no;
    }
    while (r - l > 1) {
        ll mid = r + l;
        mid /= 2;
        if (quee(1, 0, n - 1, l, mid,x)) {
            r = mid;
        }
        else if (quee(1, 0, n - 1, mid+1, r, x)) {
            l = mid;
        }
        else {
            return no;
        }
    }
    if (r < l) {
        return no;
    }
    return l;
}
void solve() {
    ll n;
    cin >> n;
    ll q;
    cin >> q;
    for (ll i = 0; i < n; i++) {
        cin >> a[i];
    }
    build(1, 0, n - 1);
    for (ll i = 0; i < q; i++) {
        string ques;
        cin >> ques;
        if (ques == "xor") {
            ll l, r, Xor;
            cin >> l >> r >> Xor;
            update(1, 0, n - 1, --l, --r, Xor);
        }
        else {
            ll l, r;
            cin >> l >> r;
            ll siz = r - l + 1;
            r--, l--;
            vector <vector<ll>> dp(siz+1, vector<ll>(8));
            dp[1][0] = ask(l,r, 0);
            for (int i = 1; i <= 7; i++) {
                dp[1][i] = min(dp[1][i - 1], ask(l, r, i-1));
            }
            ll ans = 1;
            for (ll i = 2; i <= siz; i++) {
                for (ll j = 0; j <= 7; j++) {
                    if(j>0)dp[i][j] = min(dp[i][j - 1], min(j,ask(dp[i-1][j-1], r, j - 1)));
                    if (dp[i][j] != 1e9 + 9) {
                        ans = max(ans, dp[i][j]);
                    }

                }
            }
            cout << ans << endl;
        }
    }

}
signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    ll t = 1;
    //cin >> t;
    while (t--) {
        solve();
    }
}