Test your skills (2005)

[[Gandalf]]

c++:

#include <iostream> using namespace std; int main() {    int a = 4, b = 5;    cout << a << b << endl;    cout << b << a << endl;    return 0;    cout << a << b << endl; }

Creative solution, no? And in only one extra line.

[wtd]

Ah, but you've changed the order of two of the lines.

Yes, you could have two return statements in there, but I'd consider that bad form. The ideal solution will involve no such hacks.

In fact, the final solution shouldn't be "hackish" in the slightest.

[[Gandalf]]

Ah, but you didn't mention that it had to follow good form .

Well, for that I'll have to look into it a little bit more...

[wtd]

Shame there's no easy way to swap the values in a and b.

[Martin]

c++:

#include <iostream> using namespace std; int main() {    int a = 4, b = 5;    cout << a << b << endl;    a = a + b - (b = a); // 4 + 5 - (4)    cout << a << b << endl;    return 0; }

In half of two lines. Boo yeah!

[md]

Martin wrote:

c++:

#include <iostream> using namespace std; int main() {    int a = 4, b = 5;    cout << a << b << endl;    a = a + b - (b = a); // 4 + 5 - (4)    cout << a << b << endl;    return 0; }

In half of two lines. Boo yeah!

I think you need brackets around (a+b), otherwise the second brackets get evaluated first and then b == a == 4, so a + b = 8 - 4 = 4

[Martin]

Worked in Java. I don't have a C++ compiler at work.

[md]

Hmmm... could it be that the evaluation doesn't follow normal bedmas rules? In that case it would certainly work... most interesting... Oh well, I'll give it a shot tomorrow once I get around to checking out gcc on linux

[wtd]

Martin wrote:

c++:

#include <iostream> using namespace std; int main() {    int a = 4, b = 5;    cout << a << b << endl;    a = a + b - (b = a); // 4 + 5 - (4)    cout << a << b << endl;    return 0; }

In half of two lines. Boo yeah!

Well, I did specify in response to Gandalf that the solution should not be "hackish", and I'd say this qualifies.

For instance, make this work with two strings.

c++:

#include <iostream> #include <string> using namespace std; int main() {    string a = "4", b = "5";    cout << a << b << endl;    a = a + b - (b = a); // 4 + 5 - (4)    cout << a << b << endl;    return 0; }

[[Gandalf]]

c++:

#include <iostream> #include <string> using namespace std; int main() {    string a = "4", b = "5";    cout << a << b << endl;    a.swap(b);    cout << a << b << endl;    return 0; }

Tony's program compiles and runs fine for me...

[Martin]

Alright wtd, let's hear the solution.

[wtd]

Just to make you all hate me...

c++:

#include <iostream> #include <algorithm> using namespace std; int main() {    int a = 4, b = 5;    cout << a << b << endl;    swap(a, b);    cout << a << b << endl;    return 0; }

[Martin]

It's alright wtd. I've hated you ever since I decided to buy my iMac.

[wtd]

Here's a python question.

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.

[Hikaru79]

Python:

class Student(object):    def __init__(self, name, *grades):       self.name = name       self.grades = grades       self.average_grade = sum(*grades)/len(*grades)    def __str__(self):       return "%s has an average of %.2f" % (self.name, self.average_grade)       foo = Student ( "Adrian", [40,34,40,50,69] ) print foo

This okay?

EDIT: w00t! 600 posts