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

#define LSB(x) (x & (-x))
struct BIT {
	// UPDATE      UPDATE
	// PREFIX_SUM  SUM[1, ..., k]
	// QUERY 	   SUM[i, j]
	// FIND_K      SUM[1...k] == S

	
	int size;
	vector<int> bit;

	BIT(int size) : size(size), bit(size + 2, 0) {
	}


	void update(const int& pos, const int& x) {
		for(int i = pos;  i <= size;  i += LSB(i)) {
			bit[i] += x;
		}
	}

	int prefix_sum(int k) {
		int sum = 0;
		
		for(int i = k; i > 0; i -= LSB(i)) {
			sum += bit[i];
		}
		
		return sum;
	}
  	
  	int query(int i, int j) {
  		return prefix_sum(j) - prefix_sum(i - 1);
  	}
  	
  	int find_k(int sum) {
  		int step = (1 << 30);

  		for (int i = 0; step > 0; step >>= 1) {
  			if (i + step <=  size && bit[i + step] <= sum) {
  				i += step;
  				sum -= bit[i];

  				if (sum == 0) {
  					return i;
  				}
  			}
  		}

  		return -1;
  	}
};

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

	int n, m;
	cin >> n >> m;

	BIT bit(n);

	for (int i = 1; i <= n; ++i) {
		int x;
		cin >> x;

		// update
		bit.update(i, x);
	} 

	while (m--) {
		int type, start, end, x, pos;
		cin >> type;

		switch (type) {
			case 0: {
				cin >> pos >> x;
				bit.update(pos, x);

				break;
			}

			case 1: {
				cin >> start >> end;
				cout << bit.query(start, end) << "\n";

				break;
			}


			case 2: {
				cin >> x;
				cout << bit.find_k(x) << "\n";

				break;
			}

			default: {
				cout << "wtf?";
				break;
			}
		}
	}
	
	return 0;
}