You do not seem to understand the comments you receive in your earlier threads. Re-posting will not get you much in the Monastery.
Here is a list of your troubles:
- $first and $second do not seem to be declared with my.
- @firstcolumn and @secondcolumn need to exist during the whole loop and but are being re-instantiated in each iteration. They need to be declared before the loop.
- <FILE> reads your file until and including a newline, chomp removes that newline, so $_ contains no newline. And therefore $first and $second do not contain any newlines, splitting on newlines makes no sense.
- $a and $b are also re-declared in every iteration of the loop, so their value from previous lines is forgotten every time you read a new line from the file.
This is not all but should get you started.