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#include <fstream>
using namespace std;
ifstream fin("aib.in");
ofstream fout("aib.out");
const int Nmax=1e5+5;
int v[Nmax],n;
long long aib[Nmax];
int lsb(int x) {
return x&(-x);
}
void update(int poz, int val) {
v[poz]+=val;
for (int i=poz; i<=n; i+=lsb(i)) {
aib[i]+=val;
}
}
long long query(int poz) {
long long s=0;
for (int i=poz; i>0; i-=lsb(i)) s+=aib[i];
return s;
}
int bs(int val) {
int ans=0;
long long s=0;
for (int pas=(1<<17); pas>0; pas/=2) {
if (ans+pas<n && s+aib[ans+pas]<val) {
s+=aib[ans+pas];
ans+=pas;
}
}
ans++;
s+=v[ans];
if (s!=val) ans=-1;
return ans;
}
int main()
{
int m;
fin>>n>>m;
for (int i=1; i<=n; ++i) {
int x;
fin>>x;
update(i,x);
}
for (int q=1; q<=m; ++q) {
int c,a,b;
fin>>c;
if (c==0) {
fin>>a>>b;
update(a,b);
}
else if (c==1) {
fin>>a>>b;
fout<<query(b)-query(a-1)<<endl;
}
else {
fin>>a;
fout<<bs(a)<<endl;
}
}
fin.close();
fout.close();
return 0;
}