Seems like a lot of trouble only for this. Any other solution?
It just seems like a lot of work because you wrote it in English instead of (perl) code. Also, writing the output somewhere else and then replacing the original is safer (and much less work) than modifying the original file in place.

If you have enough memory you can probably do it in one or two lines of code. But I suspect this is homework, so I'm not going to elaborate. See the -i & -p & -0 flags

updated: forgot to add the -0 flag.

"What should it profit a man, if he should win a flame war, yet lose his cool?"

In reply to Re: In place file modification by Joost
in thread In place file modification by RaduH

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.