#include <bits/stdc++.h>

using namespace std;
ifstream fin ("aib.in");
ofstream fout ("aib.out");
int n,q,v[100005],c,x,y,i,aib[100005];
void update (int p, int val)
{
    for (int j=p;j<=n;j+=(j&-j))
        aib[j]+=val;
}
int queryp (int p)
{
    int sum=0;
    for (int j=p;j>0;j-=(j&-j))
        sum+=aib[j];
    return sum;
}
int query (int st, int dr)
{
    return queryp(dr)-queryp(st-1);
}
int task3(int a)
{
    int st=1, dr=n, mij,rez=-1;
    while (st<=dr)
    {
        mij=st+(dr-st)/2;
        int s=queryp(mij);
        if (s==a) return mij;
        if (s<a) st=mij+1;
        else dr=mij-1;
    }
    return rez;
}
int main()
{
    fin>>n>>q;
    for (i=1;i<=n;i++) {fin>>v[i]; update(i,v[i]);}
    while (q--)
    {
        fin>>c;
        if (c==0)
        {
            fin>>x>>y;
            update(x,y);
        }
        if (c==1)
        {
            fin>>x>>y;
            fout<<query(x,y)<<'\n';
        }
        if (c==2)
        {
            fin>>x;
            fout<<task3(x)<<'\n';
        }
    }
    return 0;
}