#include <fstream>
#define pas(x) ((x ^ (x - 1)) & x)

using namespace std;

int aib[100003], n, m;

void Update(int poz, int val)
{
    for(int i = poz; i <= 10000; i += pas(i))
        aib[i] += val;
}

int Sum(int poz)
{
    int s = 0;
    for(int i = poz; i >= 1; i -= pas(i))
        s += aib[i];
    return s;
}

int BinarySearch(int val)
{
    int st, dr, mij, poz, s;
    st = 1;
    dr = n;
    poz = -1;
    while(st <= dr)
    {
        mij = (st + dr) / 2;
        s = Sum(mij);
        if(s == val)
        {
            poz = mij;
            dr = mij - 1;
        }
        else
            if(s > val)
                dr = mij - 1;
            else
                st = mij + 1;
    }
    return poz;
}

int main()
{
    ifstream fin("aib.in");
    ofstream fout("aib.out");
    int op, x, y;
    fin >> n >> m;
    for(int i = 1; i <= n; i++)
    {
        fin >> x;
        Update(i, x);
    }
    for(int i = 1; i <= m; i++)
    {
        fin >> op;
        if(op <= 1)
        {
            fin >> x >> y;
            if(op == 0)
                Update(x, y);
            else
                fout << Sum(y) - Sum(x - 1) << "\n";
        }
        else
        {
            fin >> x;
            fout << BinarySearch(x) << "\n";
        }
    }
    fin.close();
    fout.close();
    return 0;
}