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Re: Modify a txt file

by Marshall (Prior)
on Oct 20, 2011 at 03:18 UTC ( #932546=note: print w/ replies, xml ) Need Help??

in reply to Modify a txt file

Given that the input file has a very large number of lines, I would try to just process the file line by line (no slurping the file into a single $file_content or @lines).

Here is one way:

#/usr/bin/perl -w use strict; my $cur_num; while (<DATA>) { $cur_num = $1 if (/^(\d+)/); # new $cur num if line starts # with digits s/(\S+)$/$cur_num/; # substitute the non-spaces at the end # of the line with the cur_num print; #a blank line is not modified } =Prints 0 0 0 0 13 13 13 28 28 28 42 42 42 42 55 55 55 55 55 =cut __DATA__ 0 ASDF ASEE ASEE 13 DERG DREG 28 QWER QWER 42 WERT WERT WERT 55 QWEASD QWEASD QWEASD QWEASD

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