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0_0_8433142_14873.cpp: In function `int main()':
0_0_8433142_14873.cpp:129: error: no match for 'operator<' in 'std::operator<< [with _Traits = std::char_traits<char>](((std::basic_ostream<char, std::char_traits<char> >&)(+(+std::operator<< [with _Traits = std::char_traits<char>](((std::basic_ostream<char, std::char_traits<char> >&)(&std::cout)), ((const char*)"Case #")))->std::basic_ostream<_CharT, _Traits>::operator<< [with _CharT = char, _Traits = std::char_traits<char>](idx))), ((const char*)":")) < std::endl'
GCC/bin/../lib/gcc/mingw32/3.4.2/../../../../include/c++/3.4.2/valarray:1010: note: candidates are: std::_Expr<std::_BinClos<std::__less, std::_Constant, std::_ValArray, _Tp, _Tp>, typename std::__fun<std::__less, _Tp>::result_type> std::operator<(const _Tp&, const std::valarray<_Tp>&) [with _Tp = std::basic_ostream<char, std::char_traits<char> >]