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<TITLE>Perl Quiz of the Week #23</TITLE>
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<P><FONT SIZE=2>From: Mark Jason Dominus [<A HREF="mailto:mjd@plover.com">mailto:mjd@plover.com</A>] </FONT>
<BR><FONT SIZE=2>Sent: Wednesday, September 01, 2004 11:50 AM</FONT>
<BR><FONT SIZE=2>To: perl-qotw@plover.com</FONT>
<BR><FONT SIZE=2>Subject: [Retrieved]Perl Quiz of the Week #23</FONT>
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<P><FONT SIZE=2>IMPORTANT: Please do not post solutions, hints, or other spoilers</FONT>
<BR><FONT SIZE=2> until at least 60 hours after the date of this message.</FONT>
<BR><FONT SIZE=2> Thanks.</FONT>
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<P><FONT SIZE=2>IMPORTANT: S'il vous plat, attendez au minimum 60 heures aprs la</FONT>
<BR><FONT SIZE=2> date de ce message avant de poster solutions, indices ou autres</FONT>
<BR><FONT SIZE=2> rvlations. Merci.</FONT>
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<P><FONT SIZE=2>WICHTIG: Bitte schicken Sie keine Lsungen, Tipps oder Hinweise fr</FONT>
<BR><FONT SIZE=2> diese Aufgabe vor Ablauf von 60 Stunden nach dem Datum dieser</FONT>
<BR><FONT SIZE=2> Mail. Danke.</FONT>
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<P><FONT SIZE=2>----------------------------------------------------------------</FONT>
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<P><FONT SIZE=2>Write a program, 'parens', which gets a command line argument, n', which is an integer. The program should print all the properly-balanced strings of parentheses of length 2n. For example, given the argument '3', the program should print these five lines:</FONT></P>
<P><FONT SIZE=2> ((()))</FONT>
<BR><FONT SIZE=2> (()())</FONT>
<BR><FONT SIZE=2> (())()</FONT>
<BR><FONT SIZE=2> ()(())</FONT>
<BR><FONT SIZE=2> ()()()</FONT>
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<P><FONT SIZE=2>in some order. (The order is not important.) </FONT>
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<P><FONT SIZE=2>For the argument '1'; the output should be:</FONT>
<BR><FONT SIZE=2> </FONT>
<BR><FONT SIZE=2> ()</FONT>
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<P><FONT SIZE=2>and for argument '4', the output should be:</FONT>
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<P><FONT SIZE=2> (((())))</FONT>
<BR><FONT SIZE=2> ((()()))</FONT>
<BR><FONT SIZE=2> ((())())</FONT>
<BR><FONT SIZE=2> ((()))()</FONT>
<BR><FONT SIZE=2> (()(()))</FONT>
<BR><FONT SIZE=2> (()()())</FONT>
<BR><FONT SIZE=2> (()())()</FONT>
<BR><FONT SIZE=2> (())(())</FONT>
<BR><FONT SIZE=2> (())()()</FONT>
<BR><FONT SIZE=2> ()((()))</FONT>
<BR><FONT SIZE=2> ()(()())</FONT>
<BR><FONT SIZE=2> ()(())()</FONT>
<BR><FONT SIZE=2> ()()(())</FONT>
<BR><FONT SIZE=2> ()()()()</FONT>
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<P><FONT SIZE=2>in some order.</FONT>
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<P><FONT SIZE=2>[ ADMIN: I'm still hoping someone will step forward to write a report</FONT>
<BR><FONT SIZE=2> about expert quiz #22. - MJD ]</FONT>
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