#include <cstdio>

using namespace std;
int aib[100000];
int sp[100005];
int v[100005];
int n;
void update(int poz,int val)
{
    for(;poz<=n;poz+=poz&(-poz))
        
        aib[poz]+=val;
}
int query(int poz)
{
    int s=0;
    for(;poz>0;poz-=poz&(-poz))
        s+=aib[poz];
    return s;
}
int main()
{
    freopen("aib.in","r",stdin);
    freopen("aib.out","w",stdout);
    int m,cer,a,b,val;
    scanf("%d %d",&n ,&m);
    for(int i=1;i<=n;++i)
        {
            scanf("%d",&v[i]);
            sp[i]=sp[i-1]+v[i];
        }
    for(int i=1;i<=n;++i)
    {
        int lenght=i&(-i);
        int st=i-lenght+1;
        aib[i]=sp[i]-sp[st-1];
    }
    for(int i=1;i<=m;++i)
    {
        scanf("%d",&cer);
        if(cer==0)
        {
            scanf("%d %d",&a,&b);
            update(a,b);
        }
        if(cer==1)
        {
            scanf("%d %d",&a,&b);
            printf("%d\n",query(b)-query(a-1));
        }
        if(cer==2)
        {
            int sol=-1;
            scanf("%d",&val);
            int st=1;
            int dr=n;
            int mid=0;
            while(st<=dr)
            {
                mid=st+(dr-st)/2;;
                if(query(mid)>val)
                    dr=mid-1;
                if(query(mid)==val)
                {
                    sol=mid;
                    dr=mid-1;
                }
                if(query(mid)<val)
                {
                    st=mid+1;
                }
            }
            printf("%d\n",sol);
        }
    }
    return 0;
}