#include<iostream>
#include<fstream>
using namespace std;
const int maxx=100005;
int n,m,i,j,x,aib[maxx],tip,a,b,sum,poz;
int pas(int poz)
{
	int k=0;
	while((poz&(1<<k))==0)k++;
	return 1<<k;
}
void update(int i,int val)
{
	while(i<=n)
	{
		aib[i]+=val;
		i+=pas(i);
	}
}
int suma(int poz)
{
	int s=0;
	while(poz)
	{
		s+=aib[poz];
		poz-=pas(poz);
	}
	return s;
}
int search(int left,int right)
{
	int mij,s1;
	while(left<right)
	{
		mij=(left+right)>>1;
		s1=suma(mij);
		if(s1==a)
			return mij;
		else
			if(s1>a)
				right=mij;
			else
				left=mij+1;
	}
	if(suma(left)==a)
		return left;
	return -1;
}
int main()
{
	freopen("aib.in","r",stdin);
	freopen("aib.out","w",stdout);
	scanf("%d %d\n",&n,&m);
	for(i=1;i<=n;i++)
	{
		scanf("%d",&x);
		update(i,x);
	}
	for(j=1;j<=m;j++)
	{
		scanf("%d ",&tip);
		if(tip==0)
		{
			scanf("%d %d\n",&a,&b);
			update(a,b);
		}
		else
			if(tip==1)
			{
				scanf("%d %d\n",&a,&b);
				sum=suma(b)-suma(a-1);
				printf("%d\n",sum);
			}
			else
			{
				scanf("%d\n",&a);
				poz=search(1,n);
				printf("%d\n",poz);
			}
	}
	return 0;
}