Programming C, C++, Java, PHP, Ruby, Turing, VB
Computer Science Canada 
Programming C, C++, Java, PHP, Ruby, Turing, VB  

Username:   Password: 
 RegisterRegister   
 Test your skills (2005)
Index -> General Programming
Goto page Previous  1, 2, 3, 4, 5, 6, 7, 8, 9, 10  Next
View previous topic Printable versionDownload TopicSubscribe to this topicPrivate MessagesRefresh page View next topic
Author Message
wtd




PostPosted: Thu Nov 24, 2005 7:10 pm   Post subject: (No subject)

Try that again after:

Python:
foo.grades.append(100)
Sponsor
Sponsor
Sponsor
sponsor
wtd




PostPosted: Mon Nov 28, 2005 11:24 am   Post subject: (No subject)

wtd wrote:
Here's a python question. Smile

Python:
class Student(object):
   def __init__(self, name, *grades):
      self.name = name
      self.grades = grades
   def __str__(self):
      return "%s has an average of %.2f" % (self.name, self.average_grade)


Add a single line of code which makes the above class work correctly. It must not only work, but also accurately report the student's average grade.


The solution:

Python:
class Student(object):
   def __init__(self, name, *grades):
      self.name = name
      self.grades = grades
   def __str__(self):
      return "%s has an average of %.2f" % (self.name, self.average_grade)
   average_grade = property(lambda self: float(sum(self.grades)) / len(self.grades))
rizzix




PostPosted: Thu Dec 01, 2005 2:21 pm   Post subject: (No subject)

Write a Perl one-liner to print out the 8-12th lines of a file. (this means i should be able to execute the code with perl -e)
wtd




PostPosted: Thu Dec 01, 2005 2:40 pm   Post subject: (No subject)

code:
perl -ne "BEGIN{$c=0}print if++$c>7&&$c<13" file_name_here
rizzix




PostPosted: Thu Dec 01, 2005 3:02 pm   Post subject: (No subject)

hmm.. ok.. but may i add one more criteria?

Try and avoid the braces {}
rizzix




PostPosted: Thu Dec 01, 2005 5:14 pm   Post subject: (No subject)

Write a Perl one-liner, but avoid using any {} blocks.

The one-liner should parse a file extracting all Java-like comments where nesting comments is not allowed. (i.e you can safely assume there are no nested comments)

Sample Input:
Java:
import java.awt.*;
import javax.swing.*;

public class test {
     public static void main(String[] args) {
         // insert your application initialization code here
        JFrame frame = new JFrame("Test Application"); /* create a new JFrame */
        Dimension screenSize = frame.getToolkit().getScreenSize();
       
        frame.getContentPane().add(new JLabel("Hello World!"))
        frame.setBounds(screenSize.width/4, screenSize.height/4,
                        screenSize.width/2, screenSize.height/2);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true); /* always the last SWING method in main*/
     }
}


Sample Output:
code:
  6: insert your application initialization code here
  7: create a new JFrame
 14: always the last SWING method in main
wtd




PostPosted: Thu Dec 01, 2005 5:34 pm   Post subject: (No subject)

The simplest way I can think of does involve using the BEGIN block again.
wtd




PostPosted: Thu Dec 01, 2005 7:31 pm   Post subject: (No subject)

Language: O'Caml

code:
# let h = Hashtbl.create 10;;
val h : ('_a, '_b) Hashtbl.t = <abstr>
# Hashtbl.add h "foo" 42;;
- : unit = ()
# Hashtbl.add h "bar" 27;;
- : unit = ()
# h;;
- : (string, int) Hashtbl.t = <abstr>


Now, we know that the Hashtbl module has a "fold" function which takes a function, a hashtable, and an initial value.

The function it takes accepts three arguments: the key of the current entry, the value of the current entry, and the "accumulator" value.

Knowing this, write an expression which retrieves the keys from "h" as a list of strings.
Sponsor
Sponsor
Sponsor
sponsor
rizzix




PostPosted: Thu Dec 01, 2005 8:26 pm   Post subject: (No subject)

rizzix wrote:
Write a Perl one-liner to print out the 8-12th lines of a file. (this means i should be able to execute the code with perl -e)


The solution...

Perl:
8 .. 12 and print while (<>)
wtd




PostPosted: Thu Dec 01, 2005 8:52 pm   Post subject: (No subject)

rizzix wrote:
rizzix wrote:
Write a Perl one-liner to print out the 8-12th lines of a file. (this means i should be able to execute the code with perl -e)


The solution...

Perl:
8 .. 12 and print while (<>)


The parens shouldn't be necessary due to the way postfix loops work.
rizzix




PostPosted: Thu Dec 01, 2005 9:07 pm   Post subject: (No subject)

yep... now solve the other one Wink
rizzix




PostPosted: Mon Dec 05, 2005 8:22 pm   Post subject: (No subject)

rizzix wrote:
Write a Perl one-liner, but avoid using any {} blocks.

The one-liner should parse a file extracting all Java-like comments where nesting /* */ comments is not allowed. (i.e you can safely assume there are no nested /* */ comments)


The Solution...
Perl:
(s|.*/{2}(.*)|$1| or s|.*/\*|| .. s|\*/.*||) and s|\s*|| and printf "%3d: %s", $., $_ while <>



Breaking it down...

First we match /* to */ and extract contents within // to \n with the following regexs:
Perl:
s|.*/{2}(.*)|$1|
Perl:
s|.*/\*|| .. s|\*/.*||
Note: we use the substitution since we are only interested in the content that lies within these delimiters.

Then we trim out the whitespace off the result:
Perl:
s|\s*||
Finally we print it:
Perl:
printf "%3d: %s", $., $_
Hikaru79




PostPosted: Wed Dec 07, 2005 4:30 pm   Post subject: (No subject)

Holy mother of God. I'm oddly reminded of the bash.org quote that goes:
bash.org wrote:
s7ank: i want to be one of those guys that types
"s/j&jd//.^$ueu*///djsls/sm."
and it's a perl script that turns dog crap into gold.
md




PostPosted: Wed Dec 07, 2005 5:46 pm   Post subject: (No subject)

My mind just went *boink*. You should really put warnings up before showing code like that...
wtd




PostPosted: Tue Dec 13, 2005 5:28 am   Post subject: (No subject)

Java TYS:

code:
import java.util.*;

public class OldArrayListTest {
   public static void main(String[] args) {
      ArrayList a = new ArrayList();
      a.add("hello");
      a.add("world");
   }
}


Demonstrate the command that will compile this without warnings using the Java 1.5.0 compiler.
Display posts from previous:   
   Index -> General Programming
View previous topic Tell A FriendPrintable versionDownload TopicSubscribe to this topicPrivate MessagesRefresh page View next topic

Page 9 of 10  [ 147 Posts ]
Goto page Previous  1, 2, 3, 4, 5, 6, 7, 8, 9, 10  Next
Jump to:   


Style:  
Search: