#include <stdio.h>
#include <string.h>
#include <algorithm>

using namespace std;

const int MN = 100005;

int n,m;
int bit[MN];

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

int query(int idx)
{
    int sum = 0;

    while (idx)
    {
        sum += bit[idx];
        idx -= (idx & (-idx));
    }

    return sum;
}

int main()
{
    freopen("aib.in","r",stdin);
    freopen("aib.out","w",stdout);

     scanf("%d %d",&n,&m);

     for (int i = 1;i <= n;i++)
     {
         int x;
         scanf("%d",&x);
         update(i,x);
     }

     while (m--)
     {
         int op;

         scanf("%d",&op);

         if (op < 2)
         {
             int a,b;
             scanf("%d %d",&a,&b);

             if (!op)
                update(a,b);
           else
                printf("%d\n",query(b) - query(a - 1));
         }
       else
         {
             int a,left = 1,right = n,sol = -1;
             scanf("%d",&a);

             while (left <= right)
             {
                 int middle = (left + right) / 2,val = query(middle);

                 if (val == a)
                    sol = middle;

                 if (val > a)
                    right = middle - 1;
               else
                    left = middle + 1;
             }

             printf("%d\n",sol);
         }

     }

  return 0;
}