I am having one program, which read a line by line from a file, if the line matches for the particular pattern, then i should read nth line from a current line.

some simple example is:

open(FH,"test.txt");

while ( <FH> ) {

        ## If the line matches for this pattern, I should read 4th lin
+e from current line
        if ( $_ =~/you have to read the fourth line/ ){
                $i=0;
                while ($i<4)
                {
                        $line = <FH>;
                        $i++;
                }
                print $line;
        }
        ## If the line matches for this pattern, I should read 2nd lin
+e from current line
        elsif ( $_ =~/you have to read the second line/ ){
                $i=0;
                while ($i<2)
                {
                        $line = <FH>;
                        $i++;
                }
                print $line;
        }

}

[download]

Input:
first line
second line
third line
you have to read the fourth line
one
two
three
four
five
six
you have to read the second line
one
two
three

output:
four
two

The above coding works for me for my requirement

but i felt that the way that i have handled to read nth line from a file, is inefficient.. kindly advice some efficient way to do the above.

In reply to Reading nth line from a file by perlthirst

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