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#include <fstream>
using namespace std;
ifstream fin("aib.in");
ofstream fout("aib.out");
int n,a[100100],i,x,q,op,poz,y;
int lsb(int x){
return x&-x;
}
void update(int i,int x){
for(;i<=n;i+=lsb(i))
a[i]+=x;
}
int query(int i){
int sum=0;
for(;i;i-=lsb(i))
sum+=a[i];
return sum;
}
int cbin(int val){
int st=1,dr=n,mid;
while(st<=dr){
mid=(st+dr)/2;
if(query(mid)>=val)
dr=mid-1;
else st=mid+1;
}
if(query(st)!=val)
return -1;
return st;
}
int main(){
fin>>n>>q;
for(i=1;i<=n;i++){
fin>>x;
update(i,x);
}
for(;q--;){
fin>>op;
if(op==0){
fin>>poz>>x;
update(poz,x);
}
if(op==1){
fin>>x>>y;
fout<<query(y)-query(x-1)<<"\n";
}
if(op==2){
fin>>x;
fout<<cbin(x)<<"\n";
}
}
return 0;
}