#include <fstream>

using namespace std;
ifstream fin("aib.in");
ofstream fout("aib.out");
int aib[100001],i,n,m,c,a,b,x,st,dr,mid;
void adun(int a,int b)
{
    int i;
    for(i=a; i<=n; i+=(i&(-i)))aib[i]+=b;
}
int suma(int x)
{
    int i,s=0;
    for(i=x; i>0; i-=(i&(-i)))s+=aib[i];
    return s;
}
void cbin(int a)
{
    int st=1,dr=n,mid;
    while(st<=dr)
    {
        mid=(st+dr)/2;
        if(suma(mid)==a)
        {
            break;
        }
        if(suma(mid)>a)dr=mid-1;
        if(suma(mid)<a)st=mid+1;

    }
    if(suma(mid)!=a)fout<<-1<<'\n';
    else    fout<<mid<<'\n';
}
int main()
{
    fin>>n>>m;
    for(i=1; i<=n; i++)
    {
        fin>>x;
        adun(i,x);
    }
    for(i=1; i<=m; i++)
    {
        fin>>c;
        if(c==0||c==1)fin>>a>>b;
        else fin>>a;
        if(c==0)adun(a,b);
        if(c==1)fout<<suma(b)-suma(a-1)<<'\n';
        if(c==2)
        {
            cbin(a);
        }
    }
    return 0;
}