/*
                `-/oo+/-   ``
              .oyhhhhhhyo.`od
             +hhhhyyoooos. h/
            +hhyso++oosy- /s
           .yoooossyyo:``-y`
            ..----.` ``.-/+:.`
                   `````..-::/.
                  `..```.-::///`
                 `-.....--::::/:
                `.......--::////:
               `...`....---:::://:
             `......``..--:::::///:`
            `---.......--:::::////+/`
            ----------::::::/::///++:
            ----:---:::::///////////:`
            .----::::::////////////:-`
            `----::::::::::/::::::::-
             `.-----:::::::::::::::-
               ...----:::::::::/:-`
                 `.---::/+osss+:`
                   ``.:://///-.
*/
#include <bits/stdc++.h>
#define debug(x) cerr << #x << " " << x << '\n'
#define debugsp(x) cerr << #x << " " << x << ' '

using namespace std;

const int INF = 2e9;
const int N = 100000;

int aib[1 + N];
int n, m;

void update(int nod, int val) {
    for (int i = nod; i <= n; i += (i & (-i)))
        aib[i] += val;
}

int query(int nod) {
    int s = 0;
    for (int i = nod; i >= 1; i -= (i & (-i)))
        s += aib[i];
    return s;
}

int cautbin(int x) {
    int r, pas;
    r = 0;
    pas = 1 << 17;
    while (pas) {
        if (r + pas <= n && query(r + pas) <= x)
            r += pas;
        pas /= 2;
    }

    if (query(r) == x)
        return r;
    return -1;
} // log^2

int cautbinmaibun(int x) {
    int r, pas, cursum = 0;
    r = 0; pas = 1 << 17;

    while (pas) {
        if (r + pas <= n && cursum + aib[r + pas] <= x) {
            cursum += aib[r + pas];
            r += pas;
        }

        pas >>= 1;
    }

    if (cursum == x) return r;
    return -1;
}

int main() {
    cin >> n >> m;
    for (int i = 1; i <= n; i++) {
        int x;
        cin >> x;
        update(i, x);
    }

    for (int i = 1; i <= m; i++) {
        int t, x, y;
        cin >> t >> x;
        if (t != 2) cin >> y;

        if (t == 0)
            update(x, y);
        else if (t == 1)
            cout << query(y) - query(x - 1) << '\n';
        else cout << cautbinmaibun(x);
    }
    return 0;
}