#include <bits/stdc++.h>

using namespace std;

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

int n, m, i, task, a, b, st, dr, mid, ok;
int v[100005], aib[100005];

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

int query (int poz){
    int sol = 0;
    for (;poz>=1;poz-=(poz&(-poz))){
        sol += aib[poz];
    }
    return sol;
}

int main(){
    fin >> n >> m;
    for (i=1; i<=n; i++){
        fin >> v[i];
        update (i, v[i]);
    }
    for (i=1; i<=m; i++){
        fin >> task;
        if (task == 0 || task == 1){
            fin >> a >> b;
            if (task == 0){
                update (a, b);
            }
            else{
                fout << query (b) - query (a - 1) << "\n";
            }
        }
        else{
            fin >> a;
            st = 1, dr = n;
            ok = 0;
            while (st <= dr){
                mid = st + (dr - st)/2;
                if (query(mid) == a){
                    ok = 1;
                    fout << mid << "\n";
                    break;
                }
                else if (query(mid) > a){
                    dr = mid - 1;
                }
                else{
                    st = mid + 1;
                }
            }
            if (ok == 0){
                fout << -1 << "\n";
            }
        }
    }
    return 0;
}
//recapitulare