Select Code to Download

#!/usr/bin/perl
use strict;
...
close $inA;

print $fileBStr;

starting form the top of the file I need 1. to get the the value in th
+e 3rd
column (c1 d1)
...
4. go back to the first file (file_A.txt), get the the value in the 3r
+d column
in the second row (c2 d2) and do another round of search and insert th
+e value of d2
in the second file (file_B.txt).