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0_0_30424028_1146.cpp: In function 'constexpr double fabs(double)':
0_0_30424028_1146.cpp:16:18: error: redefinition of 'constexpr double fabs(double)'
 constexpr double fabs(double x) { return x < 0 ? -x : x; }
                  ^
In file included from GCC4.9.2/x86_64-w64-mingw32/include/c++/cmath:44:0,
                 from GCC4.9.2/x86_64-w64-mingw32/include/c++/x86_64-w64-mingw32/bits/stdc++.h:41,
                 from 0_0_30424028_1146.cpp:1:
GCC4.9.2/x86_64-w64-mingw32/include/math.h:181:31: note: 'double fabs(double)' previously defined here
   __CRT_INLINE double __cdecl fabs (double x)
                               ^
0_0_30424028_1146.cpp: In function 'constexpr bool same(double, double)':
0_0_30424028_1146.cpp:17:60: error: call to non-constexpr function 'double fabs(double)'
 constexpr bool same(double x, double y) { return fabs(x - y) < eps; }
                                                            ^