#include <bits/stdc++.h>

using namespace std;

int n, m;

class Fenwick
{
    vector <int> a;
    int _n;
    int lsb(int i)
    {
        return i & (-i);
    }
public :

    Fenwick (int n)
    {
        a.resize(n + 1);
        _n = n;
    }

    void update(int pos, int val)
    {
        for(int i = pos; i <= _n; i += lsb(i))
            a[i] += val;
    }

    int query(int pos)
    {
        int ans = 0;
        for(int i = pos; i >= 1; i -= lsb(i))
            ans += a[i];
        return ans;
    }

    int binarySearch(int x)
    {
        int r = 0, pas = 1 << 17, cursum = 0;

        while(pas)
        {
            while(r + pas <= _n  &&  cursum + a[r + pas] <= x)
            {
                cursum += a[r + pas];
                r += pas;
                if(cursum == x)
                    return r;
            }
            pas >>= 1;
        }
        return -1;
    }
};

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

    freopen("aib.in", "r", stdin);
    freopen("aib.out", "w", stdout);

    cin >> n >> m;

    Fenwick aib(n);

    for(int i = 1; i <= n; i ++)
    {
        int x;
        cin >> x;
        aib.update(i, x);
    }

    for(int i = 1; i <= m; i ++)
    {
        int cer;
        cin >> cer;
        if(cer == 0)
        {
            int a, b;
            cin >> a >> b;
            aib.update(a, b);
        }
        else if(cer == 1)
        {
            int a, b;
            cin >> a >> b;
            cout << aib.query(b) - aib.query(a - 1) << "\n";
        }
        else
        {
            int x;
            cin >> x;
            cout << aib.binarySearch(x) << "\n";
        }
    }
    return 0;
}