#include <bits/stdc++.h>
using namespace std;

#define int long long

template <class type> class SegmentTree{
    public:
        int size;
        vector<type> tree;
        type def;
        type (*marge)(type, type);

        SegmentTree(int n, type d, type (*m)(type, type)){
            size = 1;
            def = d;
            marge = m;
            n++;

            while(size < n){
                size *= 2;
            }

            tree.resize(2*size);

            for(int i = 0;i < size;i++){
                tree[size-1+i] = def;
            }

            for(int i = size-2;i >= 0;i--){
                tree[i] = marge(tree[i*2+1], tree[i*2+2]);
            }

            return;
        }

        SegmentTree(int n, type array[], type d, type (*m)(type, type)){
            size = 1;
            def = d;
            marge = m;
            n++;

            while(size < n){
                size *= 2;
            }

            tree.resize(2*size);

            for(int i = 0;i < size;i++){
                if(i < n) tree[size-1+i] = array[i];
                else tree[size-1+i] = def;
            }

            for(int i = size-2;i >= 0;i--){
                tree[i] = marge(tree[i*2+1], tree[i*2+2]);
            }

            return;
        }

        void update(int i, type val){
            i = size-1+i;
            tree[i] = val;

            while(i > 0){
                i = (i-1)/2;
                tree[i] = marge(tree[i*2+1], tree[i*2+2]);
            }

            return;
        }

        void add(int i, type val){
            i = size-1+i;
            tree[i] = tree[i] + val;

            while(i > 0){
                i = (i-1)/2;
                tree[i] = marge(tree[i*2+1], tree[i*2+2]);
            }

            return;
        }

        type get(int a, int b, int k, int l, int r){
            if(r <= a || b <= l) return def;
            if(a <= l && r <= b) return tree[k];

            type vl = get(a, b, 2*k+1, l, (l+r)/2);
            type vr = get(a, b, 2*k+2, (l+r)/2, r);

            return marge(vl, vr);
        }

        type get(int a, int b){
            return get(a, b, 0, 0, size);
        }
};

int marge(int a, int b){
    return a + b;
}

signed main(){
    int n, q;
    cin >> n >> q;

    int a[100010];

    for(int i = 0;i < n;i++) cin >> a[i];

    SegmentTree<int> seg1(n, 0, marge);
    SegmentTree<int> seg2(n, a, 0, marge);

    int t, x;
    for(int i = 0;i < q;i++){
        cin >> t >> x;
        x--;
        if(t == 1){
            seg1.update(x, 1);
        }else if(t == 2){
            seg1.update(x, 0);
        }else if(t == 3){
            seg2.add(x, 1);
        }else{
            int l = x, r = n;
            while(r - l > 1){
                int mid = (r+l)/2;
                if(seg1.get(x, mid) == (mid-x)){
                    l = mid;
                }else{
                    r = mid;
                }
            }

            int ans = seg2.get(x, l+1);

            l = -1, r = x;
            while(r - l > 1){
                int mid = (r+l)/2;
                if(seg1.get(mid, x) == (x-mid)){
                    r = mid;
                }else{
                    l = mid;
                }

            }
            ans += seg2.get(r, x);

            cout << ans << endl;

        }
    }

    return 0;
}