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#include <fstream>
#include <vector>
using namespace std;
vector < int > aib;
int n,m;
void update ( int i, int nr)
{
while(i<=n)
{
aib[i]+=nr;
i+=( i & (-i) );
}
}
int prefix_sum(int i)
{
int sum=0;
while(i>0)
{
sum+=aib[i];
i-= ( i & (-i) );
}
return sum;
}
int range_sum(int i, int j)
{
return prefix_sum(j)-prefix_sum(i-1);
}
int Lbound(int k)
{
int l=1,r=n;
while(l<r)
{
int mid=(l+r)/2,aux=prefix_sum(mid);
if(aux>=k)
r=mid;
else
l=mid+1;
}
return l;
}
int main()
{
ifstream cin("aib.in");
ofstream cout("aib.out");
int a,b,c,i;
cin>>n>>m;
aib.resize(n+1);
for(int i=1;i<=n;i++)
{
cin>>a;
update(i,a);
}
for(int i=1;i<=m;i++)
{
cin>>a;
if(a==0)
{
cin>>b>>c;
update(b,c);
}
else if(a==1)
{
cin>>b>>c;
cout<<range_sum( min(b,c) ,max (b,c) );
cout<<'\n';
}
else
{
cin>>b;
int x=Lbound(b);
if(prefix_sum(x)==b)
cout<<b;
else
cout<<"-1";
cout<<'\n';
}
}
return 0;
}