#include <fstream>
#define nmax 100004
using namespace std;
ifstream f("aib.in");
ofstream g("aib.out");
int n,m,v[nmax],op,tree[nmax],a,b;
void update (int pos,int val)
{
    while (pos<=n)
    {
        tree[pos]+=val;
        pos+=(pos&(-pos));
    }
}
long long read (int pos)
{
    long long sum=0;
    while (pos)
    {
        sum+=tree[pos];
        pos-=(pos&(-pos));
    }
    return sum;
}
int query (int a,int b)
{
    return read(b)-read(a-1);
}
int bs (int sum)
{
    int low=1,hi=n;
    while (low<hi)
    {
        int mid=(low+hi)/2;
        if (tree[mid]<sum) low=mid+1;
        else hi=mid;
    }
    if (tree[low]==sum) return low;
    return -1;
}
int main()
{
    f>>n>>m;
    for (int i=1;i<=n;i++)
    {
        f>>v[i];
        update(i,v[i]);
    }
    for (int i=1;i<=m;i++)
    {
        f>>op;
        if (op==0)
        {
            f>>a>>b;
            update(a,b);
        }
        else if (op==1)
        {
            f>>a>>b;
            g<<query(a,b)<<'\n';
        }
        else
        {
            f>>a;
            g<<bs(a)<<'\n';
        }
    }
    f.close();
    g.close();
    return 0;
}