Eroare de compilare: user.cpp:15:8: error: ‘int y1’ redeclared as different kind of symbol int x1,y1,x2,y2; ^ In file included from /usr/include/features.h:357:0, from /usr/include/i386-linux-gnu/c++/4.8/bits/os_defines.h:39, from /usr/include/i386-linux-gnu/c++/4.8/bits/c++config.h:420, from /usr/include/c++/4.8/iosfwd:38, from /usr/include/c++/4.8/ios:38, from /usr/include/c++/4.8/istream:38, from /usr/include/c++/4.8/fstream:38, from user.cpp:1: /usr/include/i386-linux-gnu/bits/mathcalls.h:243:1: error: previous declaration of ‘double y1(double)’ __MATHCALL (y1,, (_Mdouble_)); ^ user.cpp: In function ‘int main()’: user.cpp:59:12: error: cannot bind ‘std::basic_istream<char>::__istream_type {aka std::basic_istream<char>}’ lvalue to ‘std::basic_istream<char>&&’ fin>>x1>>y1>>x2>>y2; ^ In file included from /usr/include/c++/4.8/fstream:38:0, from user.cpp:1: /usr/include/c++/4.8/istream:872:5: error: initializing argument 1 of ‘std::basic_istream<_CharT, _Traits>& std::operator>>(std::basic_istream<_CharT, _Traits>&&, _Tp&) [with _CharT = char; _Traits = std::char_traits<char>; _Tp = double(double)throw ()]’ operator>>(basic_istream<_CharT, _Traits>&& __is, _Tp& __x) ^ user.cpp:61:36: warning: pointer to a function used in arithmetic [-Wpointer-arith] dr=1+min(abs(x1-x2),abs(y1-y2)); ^ user.cpp:61:38: error: call of overloaded ‘abs(double (*)(double)throw ())’ is ambiguous dr=1+min(abs(x1-x2),abs(y1-y2)); ^ user.cpp:61:38: note: candidates are: In file included from /usr/include/c++/4.8/cstdlib:72:0, from /usr/include/c++/4.8/ext/string_conversions.h:41, from /usr/include/c++/4.8/bits/basic_string.h:2815, from /usr/include/c++/4.8/string:52, from /usr/include/c++/4.8/bits/locale_classes.h:40, from /usr/include/c++/4.8/bits/ios_base.h:41, from /usr/include/c++/4.8/ios:42, from /usr/include/c++/4.8/istream:38, from /usr/include/c++/4.8/fstream:38, from user.cpp:1: /usr/include/stdlib.h:771:12: note: int abs(int) <near match> extern int abs (int __x) __THROW __attribute__ ((__const__)) __wur; ^ /usr/include/stdlib.h:771:12: note: no known conversion for argument 1 from ‘double (*)(double)throw ()’ to ‘int’ In file included from /usr/include/c++/4.8/ext/string_conversions.h:41:0, from /usr/include/c++/4.8/bits/basic_string.h:2815, from /usr/include/c++/4.8/string:52, from /usr/include/c++/4.8/bits/locale_classes.h:40, from /usr/include/c++/4.8/bits/ios_base.h:41, from /usr/include/c++/4.8/ios:42,