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There are some subtle differences between the revisions of the C standard that makes it possible to create programs that behaves differently depending on if they are compiled as C90, C99, or C11. Similarly, C++ is mostly a superset of C, but there are constructs that produce different results for C and C++.

http://ioccc.org/2015/yang/hint.html

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    After reading the post I’m going to suggest the art tag.