#include <fstream>

using namespace std;

/// aib[i] = suma elementelor din a[i - 2^k + 1, i];
/// k = numarul de biti de 0 de la sfarsitul lui i (reprezentare in baza 2)

int n, aib[100005];
ifstream fin("aib.in");
ofstream fout("aib.out");

void Update(int p, int x)
{
    while(p <= n)
    {
        aib[p] += x;
        p+= (p & (-p));
    }
}

/// suma de la a[1] la a[p]

int Suma(int p)
{
    int s = 0;
    while(p > 0)
    {
        s += aib[p];
        p -= (p & (-p));
    }
    return s;
}

/// cauta cea mai din stanga pozitie poz cu suma a[1] + ... + a[poz] = s
int CautareBinara(int p, int s)
{
    int st, dr, mij, poz;
    int suma;
    st = 1;
    dr = p;
    poz = -1;
    while(st <= dr)
    {
        mij = (st + dr) / 2;
        suma = Suma(mij);
        if(suma == s)
        {
            poz = mij;
            dr = mij - 1;
        }
        else
            if(suma > s)
                dr = mij - 1;
            else
                st = mij + 1;
    }
    return poz;
}

int main()
{
    int i, x, m, op, a, b;
    fin >> n >> m;
    for(i = 1; i <= n; i++)
    {
        fin >> x;
        Update(i, x);
    }
    while(m--)
    {
        fin >> op;
        if(!op)
        {
            fin >> a >> b;
            Update(a, b);
        }
        else
            if(op == 1)
            {
                fin >> a >> b;
                fout << (Suma(b) - Suma(a - 1)) << "\n";
            }
            else
            {
                fin >> a;
                fout << CautareBinara(n, a) << "\n";
            }

    }
    fin.close();
    fout.close();
    return 0;
}