* 'Word Encoding / ACM ICPC NWERC 2004':http://acm.pku.edu.cn/JudgeOnline/problem?id=2058
* 'Coding of Permutations / POJ':http://acm.pku.edu.cn/JudgeOnline/problem?id=1349
* 'Bits of Trinity / ACM ICPC NWERC 1999':http://www.acm.inf.ethz.ch/ProblemSetArchive/B_EU_NWRC/1999/Problems.pdf'

* 'Cuvinte / Stelele Informaticii 2003':problema/cuvinte

* Parantezari / Baraj ONI 2000
h2(#clear). 'Clear':problema/clear

* 'Game / Bursele Agora 2004':problema/game
* 'Pietre / infoarena':problema/pietre
* 'Otilia / .campion 2005':problema/otilia

* 'Playing with Matches / SGU':http://acm.sgu.ru/problem.php?contest=0&problem=153