#include <bits/stdc++.h>
#define ll long long
#define cin fin
#define cout fout
using namespace std;
ifstream fin("aib.in");
ofstream fout("aib.out");
int n, m, a, b, val;
int BIT[400099];

void update(int index, int add) {
    while (index <= n) {
        BIT[index] += add;
        index += index & (-index);
    }
}

int prefixSum(int index) {
    int result = 0;

    while (index) {
        result += BIT[index];
        index -= index & (-index);
    }

    return result;
}

int sumOfInterval(int a, int b) {
    return prefixSum(b) - prefixSum(a - 1);
}

int main() {
    ios :: sync_with_stdio(0);
    cin.tie(0);

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

    int type;
    for (int query = 1; query <= m; query++) {
        cin >> type;

        if (!type) {
            cin >> a >> b;
            update(a, b);
        } else if (type == 1) {
            cin >> a >> b;
            cout << sumOfInterval(a, b) << '\n';
        } else {
            bool found = false;
            cin >> val;
            for (int i = 1; i <= n && !found; i++)
                if (prefixSum(i) == val) {
                    cout << i << '\n';
                    found = true;
                }

            if (!found)
                cout << "-1\n";
        }
    }

    return 0;
}