//
// Created by darian on 18.06.24.
//

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


vector<ll> construct(vector<ll> &input) {
    int n = input.size();
    vector<ll> output(2 * n);
    for (int i{}; i < n; i++) {
        output[i + n] = input[i];
    }
    for (int i = n - 1; i >= 1; i--) {
        output[i] = output[2*i] + output[2*i+1];
    }
    return output;
}

ll query(int k, vector<ll> &tree, int n) {
    k += n;
    ll s = 0;
    int a = n;
    while (a <= k) {
        if (a % 2 == 1) {
            s += tree[a];
            a++;
        }
        if (k % 2 == 0) {
            s += tree[k];
            k--;
        }
        a /= 2; k /= 2;
    }
    return s;
}


void update_range(int a, int b, ll k, vector<ll> &tree, int n) {
    if (b != n - 1) {
        b += n;
        tree[b + 1] -= k;
        b++;
        b /= 2;
        for (; b >= 1; b /= 2) {
            tree[b] = tree[2 * b] + tree[2 * b + 1];
        }
    }

    a += n;
    tree[a] += k;
    a /= 2;
    for (; a  >= 1; a /= 2) {
        tree[a] = tree[2*a] + tree[2*a + 1];
    }
}


int main() {
    int n, q; cin >> n >> q;
    vector<ll> input(n);
    vector<ll> difference;
    for (int i{}; i < n; i++) {
        cin >> input[i];
        if (difference.size()) difference.push_back(input[i] - input[i - 1]);
        else difference.push_back(input[0]);
    }
    auto seg = construct(difference);
    for (int i{}; i < q; i++) {
        int t; cin >> t;
        if (t == 1) {
            int a, b; ll u; cin >> a >> b >> u;
            a--; b--;
            update_range(a, b, u, seg, n);
        } else {
            int k; cin >> k;
            k--;
            cout << query(k, seg, n) << endl;
        }
    }

}