btw, the problem is..

it only output to "groupA.txt" file, no "groupB.txt"

and "groupA.txt" file only contain this line:

4.45 3.56 4.12 3.78 4.24 3.96 4.13 4.05 3.68 4.34 average = 4.031


fawk, good thing this is the only CS class I have to take.