#include<cstdio>
using namespace std;
const int nmax = 100005;
int n,m,i,x,aib[nmax],op,a,b;
void update(int poz,int val)
{
    for(int i=poz;i<=n;i+=i&(-i)) aib[i]+=val;
}
int sum(int poz)
{
    int r=0;
    for(int i=poz;i;i-=i&(-i)) r+=aib[i];
    return r;
}
int query(int a)
{
    int lo=1,hi=n,mi,s;
    while(lo<=hi)
    {
        mi=(lo+hi)/2;
        s=sum(mi);
        if(s<a)lo=mi+1;
        if(s>a)hi=mi-1;
        if(s==a) return mi;
    }
    return -1;
}
int main()
{
    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(;m;m--)
    {
        scanf("%d",&op);
        if(op==0)
        {
            scanf("%d%d",&a,&b);
            update(a,b);
        }
        else if(op==1)
        {
            scanf("%d%d",&a,&b);
            printf("%d\n",sum(b)-sum(a-1));
        }
        else
        {
            scanf("%d",&a);
            printf("%d\n",query(a));
        }
    }
    return 0;
}