Hi,

I have an input file with 5 columns separated by single space. The first column is of width n (4 in this case). The second column is of width m (4 in this case). The rest of the columns are of variable width. I need to change the ith character (2 in this case) in second column (i<m) make it 'Y' say AND APPEND it as a third column.

Input file 
col1 col2 col3 col4 col5
1234 5678 9012 3456 7890

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Output file 
col1 col2 cYl2 col3 col4 col5
1234 5678 5Y78 9012 3456 7890

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The following program does it just fine. 
use strict;
use warnings;
my $line;
while($line=<>){
        chomp $line;
        $line =~ s/(.{5})(.{4})(.*)/$1$2 $2$3/;
        $line =~ s/(.{11}).(.*)/$1Y$2/;
        print $line."\n";
}

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My question is, is it possible to accomplish this in one s/// command? We can use \1 and \2 etc to reference the pattern we just matched, but I can't figure out how to do it here. Is it even possible?

Thanks for any help with this.

In reply to Search patern within pattern in a single substitute command by shobhit

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