#include <stdio.h>
#define N 1<<17
int n,m,v[N],aib[N];
int lsb(int x)
{
	return x & -x;
}
void update(int poz,int val)
{
	int i;
	for (i=poz; i<=n; i+=lsb(i))
		aib[i]+=val;
}
int suma(int x)
{
	int i,s=0;
	for (i=x; i>=1; i-=lsb(i))
		s+=aib[i];
	return s;
}
int cbin(int x)
{
	int i,step=N;
	for (i=0; step; step>>=1)
		if (i+step<=n && suma(i+step)<x)
			i+=step;
	i++;
	if (suma(i)==x)
		return i;
	return -1;
}
int main()
{
	freopen("aib.in","r",stdin);
	freopen("aib.out","w",stdout);
	scanf("%d%d",&n,&m);
	int i,x,y,tip;
	for (i=1; i<=n; i++)
	{
		scanf("%d",&v[i]);
		update(i,v[i]);
	}
	for (i=1; i<=m; i++)
	{
		scanf("%d",&tip);
		if (tip==0 || tip==1)
		{
			scanf("%d%d",&x,&y);
			if (!tip)
				update(x,y);
			else
				printf("%d\n",suma(y)-suma(x-1));
		}
		if (tip==2)
		{
			scanf("%d",&x);
			printf("%d\n",cbin(x));
		}
	}
	return 0;
}