#include <iostream>
#include <fstream>
using namespace std;

ifstream fin ("aib.in");
ofstream fout ("aib.out");

const int maxn = 1e5 + 5;
int Aib[maxn], n, m;

void Update(int pos, int val) {
    for (int i = pos; i <= n; i += i & -i) {
        Aib[i] += val;
    }
}

int Query(int pos) {
    int sum = 0;
    for (int i = pos; i > 0; i -= i & -i) {
        sum += Aib[i];
    }
    return sum;
}

int Bin_search(int val) {
    int l = 1, r = n, m, s;
    while (l <= r) {
        m = (l + r) >> 1;
        s = Query(m);
        if (s < val) {
            l = m + 1;
        } else if (s > val) {
            r = m - 1;
        } else return m;
    }
    return -1;
}

int main() {
    ios_base :: sync_with_stdio(false);
    int x, y, op;
    fin >> n >> m;
    for (int i = 1; i <= n; i++) {
        fin >> x;
        Update(i, x);
    }
    while (m--) {
        fin >> op >> x;
        if (op == 0) {
            fin >> y;
            Update(x, y);
        } else if (op == 1) {
            fin >> y;
            fout << Query(y) - Query(x - 1) << "\n";
        } else {
            fout << Bin_search(x) << "\n";
        }
    }
    fin.close();
    fout.close();
    return 0;
}