#include <bits/stdc++.h>

using namespace std;

ifstream fin("aib.in");
ofstream fout("aib.out");

int aib[100005], n, m;

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

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

///ret cea mai din stg poz p cu a1+a2+..+ap=s
int CautaPoz(int s)
{
    int st, dr, mid, p, suma;
    p = -1;
    st = 1;
    dr = n;
    while(st <= dr)
    {
        mid = (st + dr) / 2;
        suma = Query(mid);
        if(suma == s)
        {
            p = mid;
            dr = mid - 1;
        }
        else if(suma > s)dr = mid - 1;
        else st = mid + 1;
    }

    return p;
}

int main()
{
    int x, i, op, y, p;
    fin >> n >> m;
    for(int i = 1; i <=n ; i++)
    {
        fin >> x;
        Update(i, x);
    }
    while(m--)
    {
        fin >> op;
        if(op == 0)
        {
            fin >> p >> x;
            Update(p,x);
        }
        else if(op == 1)
        {
            fin >> x >> y;
            fout << Query(y) - Query(x-1) <<"\n";
        }
        else
        {
            fin >> p;
            fout << CautaPoz(p) <<"\n";
        }
    }
    return 0;
}