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

int A[100010],n,m,o,a,b;

void update(int pos, int val){
    while (pos <= n){
        A[pos] += val;
        pos += (pos & -pos);
    }
}

int query(int pos){
    int ans = 0;
    while (pos > 0){
        ans += A[pos];
        pos -= (pos & -pos);
    }
    return ans;
}

int interval(int st, int dr){
    return query(dr) - query(st - 1);
}

int main(){
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    ifstream cin ("aib.in");
    ofstream cout ("aib.out");
    cin >> n >> m;
    for (int i=1; i<=n; i++) {
        cin >> o;
        update(i, o);
    }
    while (m--){
        cin >> o;
        if (!o){
            cin >> a >> b;
            update(a, b);
        }
        else if (o == 1){
            cin >> a >> b;
            cout << interval(a, b) << "\n";
        }
        else{
            cin >> a;
            int st=1, dr=n, mid;
            while (st <= dr){
                mid = (st + dr)/2;
                if (query(mid) >= a) dr = mid - 1;
                else st = mid + 1;
            }
            if (query(st) == a) cout << st << "\n";
            else cout << "-1\n";
        }
    }
    return 0;
}