C++ template metaprogramming (that team was into functional programming and compile time computations). Standard, find nth Fibonacci number using recursive templates.
Sigiloso
The obvious simple solution: #include template struct FIB { enum { RESULT = FIB::RESULT + FIB::RESULT }; }; template struct FIB { enum { RESULT = 0 }; }; template struct FIB { enum { RESULT = 1 }; }; int main() { std::cout ::RESULT << std::endl; return EXIT_SUCCESS; }