View Compilation Error

0_0_12391959_4456.cpp: In function `bool equal(double, double)':
0_0_12391959_4456.cpp:17: error: call of overloaded `abs(double)' is ambiguous
GCC/bin/../lib/gcc/mingw32/3.4.2/../../../../include/stdlib.h:363: note: candidates are: int abs(int)
GCC/bin/../lib/gcc/mingw32/3.4.2/../../../../include/c++/3.4.2/cstdlib:153: note:                 long long int __gnu_cxx::abs(long long int)
GCC/bin/../lib/gcc/mingw32/3.4.2/../../../../include/c++/3.4.2/cstdlib:123: note:                 long int std::abs(long int)
0_0_12391959_4456.cpp: In function `void arrive(const node&)':
0_0_12391959_4456.cpp:49: error: `round' undeclared (first use this function)
0_0_12391959_4456.cpp:49: error: (Each undeclared identifier is reported only once for each function it appears in.)