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0_0_38178946_1831.cpp: In member function 'std::tuple<int, C, L> C::inverse(const C&) const':
0_0_38178946_1831.cpp:465:58: error: converting to 'std::tuple<int, C, L>' from initializer list would use explicit constructor 'constexpr std::tuple< <template-parameter-1-1> >::tuple(const _Elements& ...) [with _Elements = {int, C, L}]'
         if (c == a.c) return {1, {c, r * r / a.r}, null_l};
                                                          ^