#include<cstdio>
using namespace std;
#define NMAX 100005
int n,m,x,t,a,b,A[NMAX];
void update(int p, int x)
{
    int i;
    for (i=p;i<=n;i+=(i&(-i)))
        A[i]+=x;
}
int suma(int p)
{
    int i,s=0;
    for (i=p;i>0;i-=(i&(-i)))
        s+=A[i];
    return s;
}
int cb(int x)
{
    int sum,st=1,dr=n,mij;
    while (st<=dr)
    {
        mij=((st+dr)>>1);
        sum=suma(mij);
        if (sum>=x)
            dr=mij-1;
        else
            st=mij+1;
    }
    if (x==suma(st))
        return st;
    else
        return -1;
}
int main()
{
    int i;
    freopen("aib.in","r",stdin);
    freopen("aib.out","w",stdout);
    scanf("%d%d",&n,&m);
    for (i=1;i<=n;++i)
    {
        scanf("%d",&x);
        update(i,x);
    }
    for (i=1;i<=m;++i)
    {
        scanf("%d%d",&t,&a);
        switch (t)
        {
            case 0:
                scanf("%d",&b);
                update(a,b);
            break;
            case 1:
                scanf("%d",&b);
                printf("%d\n",suma(b)-suma(a-1));
            break;
            case 2:
                printf("%d\n",cb(a));
            break;
        }
    }
    return 0;
}