#include <iostream>
#include <cstdio>
using namespace std;

int tree[100000], n, m;

void update(int p, int val) {
	while (p <= n) {
		tree[p] += val;
		p += p & (-p);
	}
}

int query(int p) {
	int sum = 0;
	while (p > 0) {
		sum += tree[p];
		p -= p & (-p);
	}
	return sum;
}

int bsearch(int val) {
	int l = 1, r = n, m;
	while (r - l > 1) {
		m = (l + r) / 2;
		if (query(m) < val) l = m; else r = m;
	}
	return (query(l) == val ? l : (query(r) == val ? r : -1));
}

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

	scanf("%d %d", &n, &m);

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

	for (int i = 1; i <= m; i++) {
		scanf("%d", &op);
		switch (op) {
		case 0: scanf("%d %d", &x, &y); update(x, y); break;
		case 1: scanf("%d %d", &x, &y); printf("%d\n", query(y) - query(x - 1)); break;
		case 2: scanf("%d", &x); printf("%d\n", bsearch(x)); break;
		}
	}

	cout << endl;
	return 0;
}