#include <bits/stdc++.h>

using namespace std;

const int NMAX = 100005;
int N, M;
int aib[NMAX];

int lsb(int x)
{
    return (x & (-x));
}

void Update(int pos, int val)
{
    for (int i = pos;i <= N;i += lsb(i))
        aib[i] += val;
}

int Query(int pos)
{
    int sum = 0;
    for (int i = pos;i >= 1;i -= lsb(i))
        sum += aib[i];
    return sum;
}

int BinarySearch(int a)
{
    int left = 1, right = N, pos = -1, mid;
    while (left <= right)
    {
        mid = (left + right) / 2;
        if (Query(mid) >= a)
        {
            pos = mid;
            right = mid - 1;
        }
        else
            left = mid + 1;
    }
    if (pos != -1 && Query(pos) != a)
        pos = -1;
    return pos;
}

int main()
{
    ifstream fin("aib.in");
    ofstream fout("aib.out");
    fin >> N >> M;
    for (int i = 1;i <= N;++i)
    {
        int x;
        fin >> x;
        Update(i, x);
    }
    for (int i = 1;i <= M;++i)
    {
        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 << Query(b) - Query(a - 1) << "\n";
        }
        else
        {
            int a;
            fin >> a;
            fout << BinarySearch(a) << "\n";
        }
    }
    fin.close();
    fout.close();
    return 0;
}