#include <iostream>
#include <vector>
#include <algorithm>
#include <functional>
#include <climits>
using namespace std;

template<typename Monoid>
struct SegmentTree {
    using OP = function<Monoid(Monoid, Monoid)>;
    
    vector<Monoid> tree;
    int size;
    const OP f; // bin' operation
    const Monoid e; // neutral element
                                           
    SegmentTree(int nmemb, const Monoid &e, const OP &f):
        f(f),
        e(e)
    {
        size = 1;
        while (size < nmemb) {
            size *= 2;
        }

        tree.assign(2 * size - 1, e);
    }

    void update(int k, Monoid dat)
    {
        k += size - 1;
        tree[k] = dat;
        
        while(k > 0) {
            k = (k - 1) / 2;
            tree[k] = f(tree[2 * k + 1], tree[2 * k + 2]);
        }
    }

    // [l, r)
    Monoid query(int l, int r)
    {
        l += size - 1;
        r += size - 1;

        Monoid d = e;
        while (l < r) {
            if (l % 2 == 0) {
                d = f(d, tree[l]);
                l++;
            }
            if (r % 2 == 0) {
                r--;
                d = f(d, tree[r]);
            }

            l = (l - 1) / 2;
            r = (r - 1) / 2;
        }

        return d;
    }

    Monoid operator[] (const int k)
    {
        return query(k, k + 1);
    }
};

// 車両がつながってる区間を考える
// セグ木で、二分探索 区間の長さと総和は合う?
int main()
{
    using ll = long long;

    ll n, q;
    ll a;
    ll com, x;

    cin >> n >> q;
    SegmentTree<ll> connect(n + 1, 0, [](ll l, ll r){return l + r;});
    SegmentTree<ll> sum_a(n + 1, 0, [](ll l, ll r){return l + r;});

    for (int i = 0; i < n; i++) {
        cin >> a;
        sum_a.update(i, a);
    }

    while(q--) {
        cin >> com >> x;
        --x;

        if (com == 1) {
            connect.update(x, 1);
        }
        else if (com == 2) {
            connect.update(x, 0);
        }
        else if (com == 3) {
            sum_a.update(x, sum_a[x] + 1);
        }
        else if (com == 4) {
            ll valid, invalid, mid;
            ll l, r;

            // right
            valid = x;
            invalid = n + 1;
            while(invalid - valid > 1) {
                mid = (invalid + valid) / 2;

                if (connect.query(x, mid) >= mid - x) {
                    valid = mid;
                }
                else {
                    invalid = mid;
                }
            }
            r = valid + 1;

            // left
            valid = x;
            invalid = -1;
            while (valid - invalid > 1) {
                mid = (invalid + valid) / 2;

                if (connect.query(mid, x + 1) >= x - mid + 1) {
                    valid = mid;
                }
                else {
                    invalid = mid;
                }
            }
            l = valid;

            cout << sum_a.query(l, r) << endl;
        }
    }
}