#include <bits/stdc++.h>
using namespace std;

const int NMAX = 1e5;
int v[NMAX + 1];
int aint[4 * NMAX + 1];

void build(int node, int st, int dr) {//O(N)
    if(st == dr) {
        aint[node] = v[st];
    } else {
        int mid = (st + dr) / 2;
        build(2 * node, st, mid);
        build(2 * node + 1, mid + 1, dr);
        aint[node] = aint[2 * node] + aint[2 * node + 1];
    }
}

//O(log N)
void update(int node, int st, int dr, int pos, int val) {
    if(st == dr) {
        aint[node] += val;
    } else {
        int mid = (st + dr) / 2;
        //[st, mid], [mid + 1, dr]
        if(pos <= mid) {
            update(2 * node, st, mid, pos, val);
        } else {
            update(2 * node + 1, mid + 1, dr, pos, val);
        }
        aint[node] = aint[2 * node] + aint[2 * node + 1];
    }
}

int query(int node, int st, int dr, int x, int y) {
    if(x <= st && dr <= y) {
        return aint[node];
    } else {
        int mid = (st + dr) / 2;
        //[st, mid]
        //[mid + 1, dr]
        int L = 0, R = 0;
        if(x <= mid) {
            L = query(2 * node, st, mid, x, y);
        }
        if(mid + 1 <= y) {
            R = query(2 * node + 1, mid + 1, dr, x, y);
        }
        return L + R;
    }
}

int main() {
    ifstream cin("aib.in");
    ofstream cout("aib.out");
	int n, q;
    cin >> n >> q;
    for(int i = 1; i <= n; i++) {
        cin >> v[i];
    }
    build(1, 1, n);
    for(int i = 1; i <= q; i++) {
        int op, x, y;
        cin >> op >> x;
        if(op == 0) {
            cin >> y;
            update(1, 1, n, x, y);
        }
        if(op == 1) {
            cin >> y;
            cout << query(1, 1, n, x, y) << '\n';
        }
        if(op == 2) {
            int st = 1;
            int dr = n;
            int pos = -1;
            while(st <= dr) {
                int mid = (st + dr) / 2;
                int s = query(1, 1, n, 1, mid);
                if(s == x) {
                    pos = mid;
                    dr = mid - 1;
                } else {
                    if(s > x) {
                        dr = mid - 1;
                    } else {
                        st = mid + 1;
                    }
                }
            }
            cout << pos << '\n';
        }
    }
}