I want to simply use the two for loop variables in my awk code but I can't. Please help or guide me in the right direction.

```
for i in {30,60,100}; 
do 
   for j in {7,8}; 
   do 
       awk -v x=$i -v y=$j '{if ($NF <=x) print $0}' S_$i.txt > S_$i_$j.txt;
   done;
done

```

This was the error I received.

```
awk: fatal: cannot open file S_.txt for reading (No such file or directory). I saw this error.

```