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 <p id=toc>&nbsp;
 <h2 id=divingin>(Not) Diving In</h2>
-<p class=f>How do you know that the code you wrote yesterday still works after the changes you made today? Every seasoned programmer has war stories of an &#8220;innocent&#8221; change that couldn't <em>possibly</em> have affected that other &#8220;unrelated&#8221; module&hellip; If this sounds familiar, this chapter is for you.
-<p>In this chapter, you're going to write and debug a set of utility functions to convert to and from Roman numerals. You saw the mechanics of constructing and validating Roman numerals in <a href="regular-expressions.html#romannumerals">&#8220;Case study: roman numerals&#8221;</a>. Now step back and consider what it would take to expand that into a two-way utility.
+<p class=f>In this chapter, you're going to write and debug a set of utility functions to convert to and from Roman numerals. You saw the mechanics of constructing and validating Roman numerals in <a href="regular-expressions.html#romannumerals">&#8220;Case study: roman numerals&#8221;</a>. Now step back and consider what it would take to expand that into a two-way utility.
 <p><a href="regular-expressions.html#romannumerals">The rules for Roman numerals</a> lead to a number of interesting observations:
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 <li>There is only one correct way to represent a particular number as Roman numerals.