#include <iostream>
#include <fstream>
#include <climits>
using namespace std;
#define nmax 100005
ifstream f("aib.in");
ofstream g("aib.out");

int n,m;
int aib[nmax];

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

int querysum(int left,int right)
{
    int sum=0;
    for (int dr=right; dr; dr-=dr&(-dr))
        sum+=aib[dr];  // se aduna sumele partiale din intervalul [1,right]
    for (int dr=left-1; dr; dr-=dr&(-dr))
        sum-=aib[dr];  // se scad sumele partiale ce apartin intervalului [1,left)
    return sum; // suma din intervalul [left,right]
}

int binarysearch(int suma)
{
    int left=1,right=n,indice=INT_MAX;
    while (left<right)
    {
        int mid=(left+right)/2;
        int cursum=querysum(1,mid);
        if (cursum==suma)
        {
            indice=min(indice,mid);
            right=mid;
        }
        else if (cursum>suma)
            right=mid;
        else
            left=mid+1;
    }
    if (indice==INT_MAX)
    {
        if (querysum(1,n)==suma)
            return n;
        else
            return -1;
    }
    return indice;
}

void read()
{
    f>>n>>m;
    for (int i=1; i<=n; ++i)
    {
        int valo;
        f>>valo;
        update(valo,i);
    }
    for (int i=1; i<=m; ++i)
    {
        int typ;
        f>>typ;
        if (typ==0)
        {
            int val,poz;
            f>>poz>>val;
            update(val,poz);
        }
        else if (typ==1)
        {
            int righ,lft;
            f>>lft>>righ;
            g<<querysum(lft,righ)<<'\n';
        }
        else
        {
            int summ;
            f>>summ;
            g<<binarysearch(summ)<<'\n';
        }
    }
}

int main()
{
    read();
    return 0;
}