#include <iostream>

#define NMAX 100000

using namespace std;

int N, M, v[NMAX], T[4 * NMAX], val, pos, Start, End;

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

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

void query(int node, int st, int dr) {
    if(Start <= st && dr <= End) {
        val += T[node];
    } else {
        int mid = (st + dr) / 2;
        if (Start <= mid) {
            query(2 * node, st, mid);
        }
        if (mid + 1 <= End){
            query(2 * node + 1, mid + 1, dr);
        }
    }
}

int main()
{
    freopen("aib.in", "r", stdin);
    freopen("aib.out", "w", stdout);

    cin >> N >> M;
    for(int i = 1; i <= N; i++) {
        scanf("%d", &v[i]);
    }

    build(1, 1, N);
    int t, a, b;
    while(M--) {
        scanf("%d", &t);
        if(t == 0) {
            scanf("%d %d", &a, &b);
            val = b;
            pos = a;
            update(1, 1, N);
        } else if (t == 1) {
            scanf("%d %d", &a, &b);
            Start = a;
            End = b;
            val = 0;
            query(1, 1, N);
            printf("%d\n", val);
        } else {
            scanf("%d", &a);
            int st = 1, dr = N, mid, last = -1;
            while(st <= dr) {
                int mid = (st + dr) / 2;
                Start = 1;
                End = mid;
                val = 0;
                query(1, 1, N);
                if(a <= val) {
                    dr = mid - 1;
                    last = mid;
                } else {
                    st = mid + 1;
                }
            }
            printf("%d\n", last);
        }
    }

    return 0;
}