#include <bits/stdc++.h>
#define LAST_ONE_BIT ((poz ^ (poz - 1)) & poz)
using namespace std;
ifstream fin("aib.in");
ofstream fout("aib.out");
int n, m, aib[100100], c, a, b;

void update(int poz, int change) {
    for (; poz <= n; poz += LAST_ONE_BIT)
        aib[poz] += change;
}

int query(int poz) {
    if (poz == 0)
        return 0;
    return aib[poz] + query(poz - LAST_ONE_BIT);
}

int bin_search(int want_sum) {
    int st = 1, dr = n;
    while (st < dr) {
        int mij = (st + dr) / 2;
        if (query(mij) < want_sum)
            st = mij + 1;
        else
            dr = mij;
    }
    if (query(st) == want_sum)
        return st;
    return -1;
}

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

    for (int i = 1; i <= m; i++) {
        fin >> c;
        if (c == 0) {
            fin >> a >> b;
            update(a, b);
        } else if (c == 1) {
            fin >> a >> b;
            fout << query(b) - query(a - 1) << '\n';
        } else {
            fin >> a;
            fout << bin_search(a) << '\n';
        }
    }
    return 0;
}