#include<cstdio>
using namespace std;
int aib[100010],tip,n,m,logn,x;
void aib_update(int i,int s)
{
    for(;i<=n;i+=i&(-i)) aib[i]+=s;
}

int aib_querry(int i)
{
    int s=0;
    for(;i>=1;i-=i&(-i)) s+=aib[i];
    return s;
}
int aib_cautbin(int s)
{
    int poz=0;
    for(int i=logn;i>=0;i--)
        if((poz+(1<<i))<=n && aib[poz+(1<<i)]<s)
        {
            poz+=1<<i;
            s-=aib[poz];
        }
    return poz+1;
}
int main()
{
    freopen("aib.in","r",stdin);
    freopen("aib.out","w",stdout);
    scanf("%d%d",&n,&m);
    for(logn=1;(1<<logn)<=n;logn++);
    logn--;
    for(int i=1;i<=n;i++)
    {
        scanf("%d",&x);
        aib_update(i,x);
    }
    for(int i=1;i<=m;i++)
    {
        scanf("%d",&tip);
        int a,b;
        if(tip==0) {scanf("%d %d",&a,&b);aib_update(a,b);}
        else if(tip==1) {scanf("%d %d",&a,&b);printf("%d\n",aib_querry(b)-aib_querry(a-1));}
        else {scanf("%d",&b);a=aib_cautbin(b);if(aib_querry(a)==b) printf("%d\n",a);else printf("-1\n");}
    }
}