#include <iostream>
#include <fstream>
using namespace std;
ifstream fin("aib.in");
ofstream fout("aib.out");
int n,aib[100005];

void Update(int p, int x)
{
    while(p<=n)
    {
        aib[p]+=x;
        ///aflu cati biti de 0 sunt la finalul lui p
        p+=(p&(-p));
    }
}
int Suma(int p)
{
    int s=0;
    while(p>0)
    {
        s+=aib[p];
        p-=(p&(-p));
    }
    return s;
}
/// cauta cea mai din stanga pozitie pos cu suma a[1]+...+a[poz]=s;
int CautBin(int p, int s)
{
    int st,dr,poz,mij;
    int suma;
    st=1;
    dr=p;
    poz=-1;
    while(st<=dr)
    {
        mij=(st+dr)/2;
        suma=Suma(mij);
        if(suma==s)
        {
            poz=mij;
            dr=mij-1;
        }
        else if(suma>s) dr=mij-1;
             else st=mij+1;
    }
    return poz;
}
int main()
{
    int i,m,op,a,b,x;
    fin>>n>>m;
    for(i=1; i<=n; i++)
    {
        fin>>x;
        Update(i,x);
    }
    while(m--)
    {
        fin>>op;
        if(op==0)
        {
            fin>>a>>b;
            Update(a,b);
        }
        else if(op==1)
        {
            fin>>a>>b;
            fout<<(Suma(b)-Suma(a-1))<<"\n";
        }
        else
        {
            fin>>a;
            fout<<CautBin(n,a)<<"\n";
        }
    }
    return 0;
}