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

int n, nOp, poz;
vector <int> c;
char buff[8192];
void Read(int &nr){
	nr = 0;
	while (buff[poz] < '0' || buff[poz] > '9')
		if (++poz == 8192) {poz = 0; fread(buff, 1, 8192, stdin);}
	while (buff[poz] >= '0' && buff[poz] <= '9'){
		nr = nr *10 + (buff[poz] - '0');
		if (++poz == 8192) {poz = 0; fread(buff, 1, 8192, stdin);}
	}
}

void Actualizare(int x, int y){
	int ind = x, poz = 0;
	while (ind <= n){
		c[ind] += y;
		while ((ind & (1<<poz)) == 0) poz++;
		ind += (1<<poz);
		poz++;
	}
}

int Suma(int x){
	int s = 0, ind = x, poz = 0;
	while (ind > 0){
		s += c[ind];
		while ((ind & (1 << poz)) == 0) poz++;
		ind -= (1<<poz);
		poz++;
	}
	return s;
}

int Suma(int x, int y){return Suma(y) - Suma(x-1);}
int Cauta(int st, int dr, int x){
	int m = (st + dr) / 2;
	if (st > dr) return -1;
	if (Suma(m) == x) return m;
	if (Suma(m) > x) return Cauta(st, m-1, x);
	return Cauta(m+1, dr, x);
}

int main()
{
	freopen ("aib.in", "r", stdin), freopen("aib.out", "w", stdout);
	Read(n), Read(nOp);
	int i, x, y, op;
	c.assign(n+1, 0);
	for (i = 1; i <= n; i++){
		Read(x);
		Actualizare (i, x);
	}
	
	for (i = 0; i < nOp; i++){
		Read(op);
		switch (op){
		case 0 : 
			Read(x), Read(y);
			Actualizare(x, y);
			break;
		case 1:
			Read(x), Read(y);
			printf ("%d\n", Suma(x, y));
			break;
		case 2:
			Read(x);
			int ind = 1;
			while (x > c[ind] && ind < n) ind <<= 1;
			printf ("%d\n", Cauta(ind >> 1, ind > n ? n : ind, x));
		}
	}
	return 0;
}