Eroare de compilare: user.cpp:12:23: error: ‘int y1’ redeclared as different kind of symbol int n,a,b,k,smax=1,x1,y1,x2,y2,c,ret,x,y,xp,yp; ^ In file included from /usr/include/features.h:367:0, from /usr/include/x86_64-linux-gnu/c++/5/32/bits/os_defines.h:39, from /usr/include/x86_64-linux-gnu/c++/5/32/bits/c++config.h:482, from /usr/include/c++/5/utility:68, from /usr/include/c++/5/algorithm:60, from user.cpp:1: /usr/include/bits/mathcalls.h:251:1: note: previous declaration ‘double y1(double)’ __MATHCALL (y1,, (_Mdouble_)); ^ user.cpp: In function ‘int main()’: user.cpp:18:10: error: no match for ‘operator>>’ (operand types are ‘std::basic_istream<char>::__istream_type {aka std::basic_istream<char>}’ and ‘double(double) throw ()’) fin>>x1>>y1>>x2>>y2>>c; ^ In file included from /usr/include/c++/5/fstream:38:0, from user.cpp:3: /usr/include/c++/5/istream:120:7: note: candidate: std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(std::basic_istream<_CharT, _Traits>::__istream_type& (*)(std::basic_istream<_CharT, _Traits>::__istream_type&)) [with _CharT = char; _Traits = std::char_traits<char>; std::basic_istream<_CharT, _Traits>::__istream_type = std::basic_istream<char>] <near match> operator>>(__istream_type& (*__pf)(__istream_type&)) ^ /usr/include/c++/5/istream:120:7: note: conversion of argument 1 would be ill-formed: user.cpp:18:12: error: invalid conversion from ‘double (*)(double) throw ()’ to ‘std::basic_istream<char>::__istream_type& (*)(std::basic_istream<char>::__istream_type&) {aka std::basic_istream<char>& (*)(std::basic_istream<char>&)}’ [-fpermissive] fin>>x1>>y1>>x2>>y2>>c; ^ In file included from /usr/include/c++/5/fstream:38:0, from user.cpp:3: /usr/include/c++/5/istream:124:7: note: candidate: std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(std::basic_istream<_CharT, _Traits>::__ios_type& (*)(std::basic_istream<_CharT, _Traits>::__ios_type&)) [with _CharT = char; _Traits = std::char_traits<char>; std::basic_istream<_CharT, _Traits>::__istream_type = std::basic_istream<char>; std::basic_istream<_CharT, _Traits>::__ios_type = std::basic_ios<char>] <near match> operator>>(__ios_type& (*__pf)(__ios_type&)) ^ /usr/include/c++/5/istream:124:7: note: conversion of argument 1 would be ill-formed: user.cpp:18:12: error: invalid conversion from ‘double (*)(double) throw ()’ to ‘std::basic_istream<char>::__ios_type& (*)(std::basic_istream<char>::__ios_type&) {aka std::basic_ios<char>& (*)(std::basic_ios<char>&)}’ [-fpermissive] fin>>x1>>y1>>x2>>y2>>c; ^ In file included from /usr/include/c++/5/fstream:38:0, from user.cpp:3: /usr/include/c++/5/istream:131:7: note: candidate: std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(std::ios_base& (*)(std::ios_base&)) [with _CharT = char; _Traits = std::char_traits<char>; std::basic_istream<_CharT, _Traits>::__istream_type = std::basic_istream<char>] <near match> operator>>(ios_base& (*__pf)(ios_base&)) ^ /usr/include/c++/5/istream:131:7: note: conversion of argument 1 would be ill-formed: user.cpp:18:12: error: invalid conversion from ‘double (*)(double) throw ()’ to ‘std::ios_base& (*)(std::ios_base&)’ [-fpermissive] fin>>x1>>y1>>x2>>y2>>c; ^ In file included from /usr/include/c++/5/fstream:38:0, from user.cpp:3: /usr/include/c++/5/istream:168:7: note: candidate: std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(bool&) [with _CharT = char; _Traits = std::char_traits<char>; std::basic_istream<_CharT, _Traits>::__istream_type = std::basic_istream<char>] <near match> operator>>(bool& __n) ^ /usr/include/c++/5/istream:168:7: note: conversion of argument 1 would be ill-formed: user.cpp:18:12: warning: the address of ‘double y1(double)’ will always evaluate as ‘true’ [-Waddress]