#include <fstream>

using namespace std;

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

const int NMAX = 100005;

int n,aib[NMAX];

void update(int a,int b){
    for(int i = a;i <= n;i += i & -i)
        aib[i] += b;
}

int query(int a){
    int s = 0;
    for(int i = a;i >= 1;i -= i & -i)
        s += aib[i];
    return s;
}

int bs(int a)
{
    int st = 1,dr = n,mid;
    while(st <= dr){
        mid = st + (dr - st) / 2;
        if(query(mid) >= a)
            dr = mid - 1;
        else
            st = mid + 1;
    }
    if(query(st) == a)
    return st;
    return -1;
}

int main()
{
    int m,x,y,z;
    fin>>n>>m;
    for(int i = 1;i <= n;i++)
    {
        fin>>x;
        update(i,x);
    }
    for(int i = 1;i <= m;i++)
    {
        fin>>x>>y;
        if(x != 2)
            fin>>z;
        if(x == 0)
            update(y,z);
        if(x == 1)
            fout<<query(z) - query(y - 1)<<"\n";
        if(x == 2)
        {
            fout<<bs(y)<<"\n";
        }
    }
    return 0;
}