📄 ch02_13.htm

📁 by Randal L. Schwartz and Tom Phoenix ISBN 0-596-00132-0 Third Edition, published July 2001. (See
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<html><head><title>Exercises (Learning Perl, 3rd Edition)</title><link rel="stylesheet" type="text/css" href="../style/style1.css" /><meta name="DC.Creator" content="Randal L. Schwartz and Tom Phoenix" /><meta name="DC.Format" content="text/xml" scheme="MIME" /><meta name="DC.Language" content="en-US" /><meta name="DC.Publisher" content="O'Reilly &amp; Associates, Inc." /><meta name="DC.Source" scheme="ISBN" content="0596001320L" /><meta name="DC.Subject.Keyword" content="stuff" /><meta name="DC.Title" content="Learning Perl, 3rd Edition" /><meta name="DC.Type" content="Text.Monograph" /></head><body bgcolor="#ffffff"><img alt="Book Home" border="0" src="gifs/smbanner.gif" usemap="#banner-map" /><map name="banner-map"><area shape="rect" coords="1,-2,616,66" href="index.htm" alt="Learning Perl, 3rd Edition" /><area shape="rect" coords="629,-11,726,25" href="jobjects/fsearch.htm" alt="Search this book" /></map><div class="navbar"><table width="684" border="0"><tr><td align="left" valign="top" width="228"><a href="ch02_12.htm"><img alt="Previous" border="0" src="../gifs/txtpreva.gif" /></a></td><td align="center" valign="top" width="228"><a href="index.htm"></a></td><td align="right" valign="top" width="228"><a href="ch03_01.htm"><img alt="Next" border="0" src="../gifs/txtnexta.gif" /></a></td></tr></table></div><h2 class="sect1">2.13. Exercises</h2><p>See <a href="appa_01.htm#lperl3-APP-A-SECT-1">Section A.1, "Answers to Chapter 2 Exercises "</a> for answers to the followingexercises:</p><ol><li><p>[5] Write a program that computes the circumference of a circle witha radius of 12.5. Circumference is 2<img align="absmiddle" src="figs/U03C0.gif" /> times the radius(approximately 2 times 3.141592654). The answer you get should beabout 78.5.</p></li><li><p>[4] Modify the program from the previous exercise to prompt for andaccept a radius from the person running the program. So, if the userenters 12.5 for the radius, she should get the same number as in theprevious exercise.</p></li><li><p>[4] Modify the program from the previous exercise so that, if theuser enters a number less than zero, the reported circumference willbe zero, rather than negative.</p></li><li><p>[8] Write a program that prompts for and reads two numbers (onseparate lines of input) and prints out the product of the twonumbers multiplied together.</p></li><li><p>[8] Write a program that prompts for and reads a string and a number(on separate lines of input) and prints out the string the number oftimes indicated by the number on separate lines. (Hint: Use the"x" operator.) If the user enters "fred" and"3," the output should be three lines, each saying"fred". If the user enters "fred" and"299792," there may be a lot of output.<a name="INDEX-258" /></p></li></ol><hr width="684" align="left" /><div class="navbar"><table width="684" border="0"><tr><td align="left" valign="top" width="228"><a href="ch02_12.htm"><img alt="Previous" border="0" src="../gifs/txtpreva.gif" /></a></td><td align="center" valign="top" width="228"><a href="index.htm"><img alt="Home" border="0" src="../gifs/txthome.gif" /></a></td><td align="right" valign="top" width="228"><a href="ch03_01.htm"><img alt="Next" border="0" src="../gifs/txtnexta.gif" /></a></td></tr><tr><td align="left" valign="top" width="228">2.12. The defined Function</td><td align="center" valign="top" width="228"><a href="index/index.htm"><img alt="Book Index" border="0" src="../gifs/index.gif" /></a></td><td align="right" valign="top" width="228">3. Lists and Arrays </td></tr></table></div><hr width="684" align="left" /><img alt="Library Navigation Links" border="0" src="../gifs/navbar.gif" usemap="#library-map" /><p><p><font size="-1"><a href="copyrght.htm">Copyright &copy; 2002</a> O'Reilly &amp; Associates. All rights reserved.</font></p><map name="library-map"><area shape="rect" coords="1,0,85,94" href="../index.htm"><area shape="rect" coords="86,1,178,103" href="../lwp/index.htm"><area shape="rect" coords="180,0,265,103" href="../lperl/index.htm"><area shape="rect" coords="267,0,353,105" href="../perlnut/index.htm"><area shape="rect" coords="354,1,446,115" href="../prog/index.htm"><area shape="rect" coords="448,0,526,132" href="../tk/index.htm"><area shape="rect" coords="528,1,615,119" href="../cookbook/index.htm"><area shape="rect" coords="617,0,690,135" href="../pxml/index.htm"></map></body></html>
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