To find and count a repeating pattern in a line

punitpawar has asked for the wisdom of the Perl Monks concerning the following question:

Hello,
I wanted to know if there is any way by using regular expression to count the occurrences of a repeating pattern in a line ?
here is the problem statement
Given a log file:
some garbage...from:123.54,78.21...more garbage..to:56,82,124.54...more some more garbage...from:11.54,45.84...garbage..to:115.87,98.65 ... Assumption: these coordinates will always appear in sequence: from ... to... from ... to... But these from - to pair may or may not be on same line
Write a script to return pairs of (from, to) coordinates.
The only way I could think of was by splitting the line....But I feel there should be a better way. here is my code below

#!/usr/bin/perl
use Data::Dumper;

open(FH,"<abc.txt")or die EXPR;
     
while (<FH>) {
    
   my @words = split(/ /,$_);
   
   foreach (@words) {
    
    if ($_=~/from:(\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})/) {
       
        print "$1- \n";
      
    }elsif ($_ =~/to:(\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})/){
       
       print "$1 \n";
       
       
   }
   
   
   }
}

close (FH);
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This is the sample input file abc.txt

hshhhgljlkjglgkjj from:198.18.66.5 aegighighighilg to:198.18.66.6 iiuf
+duifuiuih from:198.18.66.7
hiihhj to:198.18.66.8 hhouhoho from:198.18.66.9 igilgojhjh to:198.18.6
+6.10 igighliho
from:198.18.66.11 highighioouhouhhhoh  to:198.18.66.12
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And the output I am expecting is


198.18.66.5 ,198.18.66.6
198.18.66.7 ,198.18.66.8
198.18.66.9 ,198.18.66.10
198.18.66.11 ,198.18.66.12
[download]

Comment on To find and count a repeating pattern in a line Select or Download Code

Replies are listed 'Best First'.
Re: To find and count a repeating pattern in a line by poj (Abbot) on Feb 08, 2016 at 20:05 UTC
#!perl use strict; my @from =(); my @to =(); my $re = qr/\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}/; while (<DATA>){ next unless /(?:to\|from):$re/; push @from,($_ =~ /from:($re)/g); push @to, ($_ =~ /to:($re)/g); } for (@from){ print "$_ ,".(shift @to)."\n" } __DATA__ hshhhgljlkjglgkjj from:198.18.66.5 aegighighighilg to:198.18.66.6 iiuf +duifuiuih from:198.18.66.7 hiihhj to:198.18.66.8 hhouhoho from:198.18.66.9 igilgojhjh to:198.18.6 +6.10 igighliho from:198.18.66.11 highighioouhouhhhoh to:198.18.66.12 [download] poj	[reply] [d/l]
Re: To find and count a repeating pattern in a line by neilwatson (Priest) on Feb 08, 2016 at 19:47 UTC
I encourage wisdom seekers to present some sample data and use Test::More to present a better picture of their goal. Neil Watson watson-wilson.ca	[reply]