#include <bits/stdc++.h>
using namespace std;
ifstream fin("aib.in");
ofstream fout("aib.out");
#define lsb(i) (i & (-i))
const int NMAX = 1e5 + 5;
int aib[NMAX], n, m;

void update(int poz, int val)
{
    for(int i = poz; i <= n; i += lsb(i))
        aib[i] += val;
}

int sum(int st, int dr)
{
    int sum_dr = 0, sum_st = 0;
    for(int i = dr; i >= 1; i -= lsb(i))
        sum_dr += aib[i];
    for(int i = st - 1; i >= 1; i -= lsb(i))
        sum_st += aib[i];
    return sum_dr - sum_st;
}

int caut_bin(int val)
{
    int st = 1, dr = n;
    while(st <= dr)
    {
        int mid = (st + dr) / 2;
        if(sum(1, mid) == val)
            return mid;
        else if(sum(1, mid) < val)
            st = mid + 1;
        else
            dr = mid - 1;
    }
    return -1;
}

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

    while(m--)
    {
        int op;
        fin >> op;
        if(op == 0)
        {
            int a, b;
            fin >> a >> b;
            update(a, b);
        }
        else if(op == 1)
        {
            int a, b;
            fin >> a >> b;
            fout << sum(a, b) << "\n";
        }
        else
        {
            int a;
            fin >> a;
            fout << caut_bin(a) << "\n";
        }
    }

    return 0;
}