#include<cstdio>
using namespace std;
const int MAXN=100005;
int n,m;
int arb[MAXN];
int sum(int i)
{
	int suma=0;
	while (i>0)
	{
		suma+=arb[i];
		i-=(i&-i);
	}
	return suma;
}
void update(int pos, int val)
{
	while (pos<=n && pos)
	{
		arb[pos]+=val;
		pos+=(pos& -pos);
	}
}
int query(int a, int b)
{
	return sum(b)-sum(a-1);
}
int binary_search(int suma)
{
	int pos=-1,left=1,right=n,mid=0;
	while (left<=right)
	{
		mid=(left+right)/2;
		if (sum(mid)==suma)
		{
			pos=mid;
			while (suma==sum(pos-1))
			{
				--pos;
			}
			break;
		}
		else if (suma<sum(mid))
		{
			right=mid-1;
		}
		else if (suma>sum(mid))
		{
			left=mid+1;
		}
	}
	return pos;
}
int main()
{
	int i,x,opt,a,b;
	freopen("aib.in","r",stdin);
	freopen("aib.out","w",stdout);
	scanf("%d%d",&n,&m);
	for (i=1; i<=n; ++i)
	{
		scanf("%d",&x);
		update(i,x);
	}
	for (i=1; i<=m; ++i)
	{
		scanf("%d%d",&opt,&a);
		if (!opt)
		{
			scanf("%d",&b);
			update(a,b);
		}
		else if (opt==1)
		{
			scanf("%d",&b);
			printf("%d\n",query(a,b));
		}
		else if (opt==2)
		{
			printf("%d\n",binary_search(a));
		}
	}
	return 0;
}