Category Archives: Puzzle

IEEE-754 brain teaser

Posted on 2013/06/27 by niemeyer

Here is a small programming brain teaser for the weekend: Assume uf is an unsigned integer with 64 bits that holds the IEEE-754 representation for a binary floating point number of that size. The questions are:

Posted in C/C++, Erlang, Go, Haskell, Java, Math, Perl, Puzzle, Python, Ruby, Snippet | 7 Comments

Cut the rope, a tablet is NOT a laptop

Posted on 2011/07/19 by niemeyer

Back in 2009 I quickly talked about the obvious revolution in computing that was rolling in the form of mobile phone as computer, and mentioned as well the fact that touch-based interfaces were going to dominate the marketplace because of … Continue reading →

Posted in Article, Design, Mobile, Puzzle | 3 Comments

Breaking into an Android password manager – Practice

Posted on 2009/12/05 by niemeyer

In the last post, we’ve seen some security issues which exist in the Android password manager gbaSafe version 1.1.0a, by analyzing the security description provided in its web site. As described there, even though the system depends on a “master … Continue reading →

Posted in Architecture, Mobile, Puzzle, Security | 8 Comments

Breaking into an Android password manager – Theory

Posted on 2009/12/01 by niemeyer

For some time now I’ve been wanting to research more deeply about the internals of Android. Until now, though, this was just a sentiment. Then, a couple of weeks ago I’ve finally managed to replace my iPhone for an Android … Continue reading →

Posted in Architecture, Java, Mobile, Puzzle, Security | 5 Comments

Python module for Constraint Solving Problems

Posted on 2005/07/07 by niemeyer

The constraint module presented in PyCon Brasil and later on EuroPython 2005 is now available. Here is a trivial example, solving the classical rooks problem: problem = Problem() numpieces = 8 cols = range(numpieces) rows = range(numpieces) problem.addVariables(cols, rows) for … Continue reading →

Posted in Conference, Project, Puzzle, Python | 5 Comments

Problem of the Week at University of Massachusetts

Posted on 2005/04/10 by niemeyer

University of Massachusetts has a very nice Problem of the Week service where they post a new math related problem every monday. At that time they report the percentage of people that correctly answered the question as well. To submit … Continue reading →

Posted in Math, Puzzle, Python | Leave a comment

Petals Around the Rose

Posted on 2005/04/10 by niemeyer

Petals Around the Rose is an interesting brain teaser. Here is a copy of the game description: The name of the game is Petals Around the Rose. The name of the game is important. The computer will roll five dice … Continue reading →

Posted in Puzzle | Leave a comment