Eroare de compilare: user.cpp:6:22: error: ‘int y1’ redeclared as different kind of symbol int i, n, x1, x2, x, y1, y2, y, mini, na, nr; ^ 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:48:8: error: cannot bind ‘std::basic_istream<char>::__istream_type {aka std::basic_istream<char>}’ lvalue to ‘std::basic_istream<char>&&’ fin>>x1>>y1; ^ 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:69:10: error: invalid operands of types ‘int’ and ‘double(double)throw ()’ to binary ‘operator-’ y=y2-y1; ^