Due to confusion about the semantic interpretation of the modulo operator and the integer range: the C code is to be interpretet as C99 and the inter range for all integers is asumed to be 32 bit.

It is planned to publish an STTT special section on RERS 2016. Winning and interesting approaches will be invited to publish a paper on their challenge approach and contribution. Each participant is invited to shortly present his or her approach on the challenge at the RERS meeting.

The bronze, silver and gold problems mark the level of difficulty. One Achievement is possible for each color, the most difficult level will be awarded. For further information please take a look at the rewards and achievements page.

For further information about the code layout please read the Java-code and C99-code description. Other useful information can be found on the problem description page. Please not that the syntax and semantic of the properties varies from the parallel problems.

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The problems are provided as tarball containing all reachability problems. Detailed solutions for the problems (with counterexamples) can be donwloaded as a zip file.

The table provides an overview of the difficulty of each problem.

size	plain, simple	arithmetic, medium	data structures, hard
small	Problem10	Problem11	Problem12
medium	Problem13	Problem14	Problem15
large	Problem16	Problem17	Problem18

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Please remember that the problems can not be compiled as they are provided. Please read the Java-code and C99-code description for compilation assistance.