#include <algorithm>
using namespace std;

#define DIM 100005

int aib[DIM];
int n,m;

inline int lsb (int x)
{
    return x&(-x);
}

inline void update (int poz,int val)
{
    for ( ; poz<=n; poz+=lsb (poz))
        aib[poz]+=val;
}

void read ()
{
    int i,x;

    scanf ("%d%d",&n,&m);
    for (i=1; i<=n; ++i)
    {
        scanf ("%d",&x);
        update (i,x);
    }
}

inline int query (int poz)
{
    int sum;

    for (sum=0; poz; poz-=lsb (poz))
        sum+=aib[poz];

    return sum;
}

inline int cbin (int val)
{
    int st,dr,mij,sol;

    sol=0;
    for (st=1, dr=n; st<=dr; )
    {
        mij=(st+dr)/2;
        if (query (mij)>=val)
        {
            sol=mij;
            dr=mij-1;
        }
        else
            st=mij+1;
    }
    if (query (sol)==val)
        return sol;
    return -1;
}

void solve ()
{
    int i,tip,x,y;

    for (i=1; i<=m; ++i)
    {
        scanf ("%d",&tip);
        if (!tip)
        {
            scanf ("%d%d",&x,&y);
            update (x,y);
        }
        else if (tip==1)
        {
            scanf ("%d%d",&x,&y);
            printf ("%d\n",query (y)-query (x-1));
        }
        else
        {
            scanf ("%d",&x);
            printf ("%d\n",cbin (x));
        }
    }
}

int main ()
{
    freopen ("aib.in","r",stdin);
    freopen ("aib.out","w",stdout);

    read ();
    solve ();

    return 0;
}