#include <iostream>
#include <fstream>
#define maxn 100002
using namespace std;

ifstream fin("aib.in");
ofstream fout("aib.out");

int n, q;
int tree[maxn+2];

void update(int pos, int val)
{
    while(pos<=n)
    {
        tree[pos]+=val;
        pos+=(pos&-pos);
    }
}

int query(int pos)
{
    int sum=0;
    while(pos>0)
    {
        sum=sum+tree[pos];
        pos=pos-(pos&-pos);
    }
    return sum;
}

int idsearch(int x)
{
    int bitmask=1, val=x, idx=0;
    while(bitmask*2<=n)
    {
        bitmask<<=1;
    }
    while(bitmask!=0)
    {
        int mid=idx+bitmask;
        bitmask>>=1;
        if(mid>n)
            continue;
        if(val>=tree[mid])
        {
            idx=mid;
            val=val-tree[mid];
        }
    }
    if(val!=0)
        return -1;
    else
        return idx;
}

int main()
{
    int val, op, pos1, pos2;
    fin>>n>>q;
    for(int i=1; i<=n; i++)
    {
        fin>>val;
        update(i,val);
    }
    while(q--)
    {
        fin>>op;
        if(op==0)
        {
            fin>>pos1>>val;
            update(pos1,val);
        }
        else if(op==1)
        {
            fin>>pos1>>pos2;
            fout<<query(pos2)-query(pos1-1)<<'\n';
        }
        else
        {
            fin>>val;
            fout<<idsearch(val)<<'\n';
        }
    }
    return 0;
}