On this page you can see results and code from past rounds of Google Code Jam, and you can try the problems for yourself. If you're new to Code Jam, try following the Quick-Start Guide.
If you're new to programming contests, we highly recommend starting with the least difficult problems and moving up from there as you get more confident. Beware: the round that has the easiest problem A may have a very difficult problem B! As you get used to the platform, you can check how many people solved each problem in the "Submissions" box to the left of the dashboard, and use that as a rough gauge of difficulty.
Here are some choice problems for new competitors:
Remember, if you get stuck you can look at someone else's solution (click a "solutions" link below) or join our mailing list and ask for help. If you're done with these problems and looking for more, look for early rounds (Qualification, Round 1, maybe Round 2) and look at the first problems (A, B). Then see how many of the competitors solved them.
You can click a "solutions" link below, but those aren't really indexed in a helpful way. You can find solutions grouped by language, author and country at http://go-hero.net/jam, a site written by contestant foxlit.
| EuroPython 2012 | scores | solutions | Jul 05 2012 | 2hr |
| Round 3 | scores | solutions | analysis | Jun 09 2012 | 2hr 30min |
| Round 2 | scores | solutions | analysis | May 26 2012 | 2hr 30min |
| Round 1C | scores | solutions | analysis | May 06 2012 | 2hr 30min |
| Round 1B | scores | solutions | analysis | May 05 2012 | 2hr 30min |
| Round 1A | scores | solutions | analysis | Apr 28 2012 | 2hr 30min |
| Qualification Round | scores | solutions | analysis | Apr 13 2012 | 25hr |
| Code Jam Korea 2012 결선 라운드 | scores | solutions | Apr 07 2012 | 4hr | |
| Code Jam Korea 2012 본선 2차 라운드 | scores | solutions | Mar 10 2012 | 3hr | |
| Code Jam Korea 2012 본선 라운드 | scores | solutions | Mar 03 2012 | 3hr | |
| Code Jam Korea 2012 예선 라운드 | scores | solutions | analysis | Feb 25 2012 | 12hr |
| Code Jam Japan 2011 決勝 | scores | solutions | analysis | Oct 08 2011 | 3hr |
| Code Jam Japan 2011 予選 | scores | solutions | analysis | Oct 01 2011 | 6hr |
| Code Jam Japan 2011 練習問題 | scores | solutions | Aug 01 2011 | 2hr |
| EuroPython 2011 | scores | solutions | Jun 21 2011 | 3hr 10min |
| World Finals | scores | solutions | analysis | Jul 29 2011 | 4hr |
| Round 3 | scores | solutions | analysis | Jun 11 2011 | 2hr 30min |
| Round 2 | scores | solutions | analysis | Jun 04 2011 | 2hr 30min |
| Round 1C | scores | solutions | analysis | May 22 2011 | 2hr 30min |
| Round 1B | scores | solutions | analysis | May 21 2011 | 2hr 30min |
| Round 1A | scores | solutions | analysis | May 21 2011 | 2hr 30min |
| Qualification Round | scores | solutions | analysis | May 06 2011 | 24hr |
| Online Competition | scores | solutions | Feb 24 2011 | 3hr | |
| Qualification Round | scores | solutions | analysis | Feb 17 2011 | 6hr |
| World Finals | scores | solutions | analysis | Jul 30 2010 | 4hr |
| Round 3 | scores | solutions | analysis | Jun 12 2010 | 2hr 30min |
| Round 2 | scores | solutions | analysis | Jun 05 2010 | 2hr 30min |
| Round 1C | scores | solutions | analysis | May 23 2010 | 2hr 30min |
| Round 1B | scores | solutions | analysis | May 22 2010 | 2hr 30min |
| Round 1A | scores | solutions | analysis | May 22 2010 | 2hr 30min |
| Qualification Round | scores | solutions | analysis | May 07 2010 | 24hr |
| Online Competition | scores | solutions | analysis | Mar 22 2010 | 3hr |
| Qualification Round | scores | solutions | Mar 15 2010 | 12hr |
| World Finals | scores | solutions | analysis | Nov 13 2009 | 4hr |
| Round 3 | scores | solutions | analysis | Oct 10 2009 | 2hr 30min |
| Round 2 | scores | solutions | analysis | Sep 26 2009 | 2hr 30min |
| Round 1C | scores | solutions | analysis | Sep 13 2009 | 2hr 30min |
| Round 1B | scores | solutions | analysis | Sep 12 2009 | 2hr 30min |
| Round 1A | scores | solutions | analysis | Sep 12 2009 | 2hr 30min |
| Qualification Round | scores | solutions | analysis | Sep 02 2009 | 26hr |
| World Finals | scores | solutions | analysis | Nov 14 2008 | 3hr |
| EMEA Semifinal | scores | solutions | analysis | Oct 06 2008 | 2hr |
| AMER Semifinal | scores | solutions | analysis | Sep 29 2008 | 2hr |
| APAC Semifinal | scores | solutions | analysis | Sep 22 2008 | 2hr |
| Round 3 | scores | solutions | analysis | Aug 09 2008 | 2hr |
| Round 2 | scores | solutions | analysis | Aug 02 2008 | 2hr |
| Round 1C | scores | solutions | analysis | Jul 27 2008 | 2hr |
| Round 1B | scores | solutions | analysis | Jul 26 2008 | 2hr |
| Round 1A | scores | solutions | analysis | Jul 26 2008 | 2hr |
| Qualification Round | scores | solutions | analysis | Jul 16 2008 | 24hr |
| Practice Contest | scores | solutions | Sep 13 2008 | 2hr | |
| Code Jam Beta 2008 | scores | solutions | Apr 16 2008 | 2hr | |
| Practice Problems | scores | solutions | Apr 12 2008 | 17hr 20min |
TopCoder runs regular algorithm competitions called SRMs (Single Round Matches) that anyone can participate in. They also run High School matches and the annual TopCoder Open. You can practice with their old rounds; start with Division 2 if you're new. They also have a variety of other, longer-term programming competitions. Warning: you'll only be able to use Java, C++, C# or Visual Basic.
If you're a university or college student, your school may have a team that competes in the ACM ICPC. Some teams have regular practices, tryouts and local contests; if yours doesn't, maybe you can start something. You can try to solve problems that have been used in old ACM contests (local and global) on your own at their Online Judge. Warning: you'll only be able to use C, C++, Java and PASCAL.
The Sphere Online Judge also hosts a lot of problems.