#include<bits/stdc++.h>

using namespace std;

#define dbg(x) (cout<<#x<<" = "<<(x)<<'\n')

typedef long long int lld;
const int INF = (1LL << 30) - 1;
const lld LINF = (1LL << 62) - 1;

template<class T>
class FenwickTree {
private:
	int N;
	vector<T> AIB;

	void upd(const int &position, const T &value) {
		for (int i = position; i <= N; i += i & (-i))
			AIB[i] += value;
	}

	T qry(const int &position) {
		T answer = 0;
		for (int i = position; i >= 1; i -= i & (-i))
			answer += AIB[i];
		return answer;
	}

public:
	FenwickTree() {
		this->N = 0;
		this->AIB.clear();
	}

	FenwickTree(const int &N) {
		this->N = N;
		this->AIB.resize(N + 5);
	}

	FenwickTree(const int &N, const vector<T> &V) {
		this->N = N;
		this->AIB.resize(N + 5);
		int index = 1;
		for (auto x : V) {
			upd(index, x);
			index++;
		}
	}

	FenwickTree(const int &N, const T *V) {
		this->N = N;
		this->AIB.resize(N + 5);
		for (int index = 1; index <= N; index++)
			upd(index, V[index]);
	}

	FenwickTree(const int &N, const T *V, const int &offset) {
		this->N = N;
		this->AIB.resize(N + 5);
		for (int index = 1; index <= N; index++)
			upd(index, V[offset - 1 + index]);
	}

	void update(const int &position, const T &value) {
		upd(position, value);
	}

	T query(const int &position) {
		return qry(position);
	}

	T query(const int &p0, const int &p1) {
		return qry(p1) - qry(p0 - 1);
	}

	T search(T sum) {
		int step = 0;

		for (step = 1; step < N; step *= 2);

		for (int i = 0; step >= 1; step /= 2)
			if (i + step <= N && sum >= AIB[i + step]) {
				i += step;
				sum -= AIB[i];
				if (sum == 0)
					return i;
			}

		return -1;
	}
};

int N, M;
FenwickTree<int> AIB;

int main() {
	cin.sync_with_stdio(false);

	#ifndef ONLINE_JUDGE
	freopen("aib.in", "r", stdin);
	freopen("aib.out", "w", stdout);
	#endif

	scanf("%d%d", &N, &M);

	AIB = FenwickTree<int>(N);

	for (int i = 1, x; i <= N; i++) {
		scanf("%d", &x);
		AIB.update(i, x);
	}

	for (int i = 1, op, a, b; i <= M; i++) {
		scanf("%d", &op);

		if (op == 0) {
			scanf("%d%d", &a, &b);
			AIB.update(a, b);
			continue;
		}

		if (op == 1) {
			scanf("%d%d", &a, &b);
			printf("%d\n", AIB.query(a, b));
			continue;
		}

		if (op == 2) {
			scanf("%d", &a);
			printf("%d\n", AIB.search(a));
			continue;
		}
	}

	return 0;
}