Not at all - I understand. One of the most important skills to have as a programmer is choosing the right tool for the right job. That's not to say Java can't d

Not at all - I understand. One of the most important skills to have as a programmer is choosing the right tool for the right job. That's not to say Java can't do what you want, but you might find it's better designed for tackling large abstract problems than algorithmic and mathematical ones. For example, check out this list of people who have completed 250 or more problems (only works if you're logged in): http://projecteuler.net/index.php?section=scores&show=veterans http://projecteuler.net/index.php?section=scores&show=ve... Correlation isn't causation and all that, but this shows you the tools that the people who finish all the problems want to use are, in order, C/C++, Python, Java, and Mathematica. In the end, though, it's really a question of what your goal is. If you want to learn Java, then learn Java (but I would consider learning it using problems better suited to it). If you want to solve Project Euler problems, you'll have your work cut out for you just figuring out good algorithms; it's best to do it in the language that will give you the least trouble. Incidentally, while Python automatically turns large numbers into digit arrays, if you stick with Java you might find its equivalent BigInteger class useful: http://download.oracle.com/javase/1,5.0/docs/api/java/math/BigInteger.html http://download.oracle.com/javase/1,5.0/docs/api/java/math/B...