Eroare de compilare: main.cpp:96:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type] 96 | main() | ^~~~ main.cpp: In instantiation of 'std::istream& operator>>(std::istream&, std::vector<_Tp>&) [with A = std::pair<double, double>; std::istream = std::basic_istream<char>]': main.cpp:66:10: required from here main.cpp:20:87: error: no match for 'operator>>' (operand types are 'std::istream' {aka 'std::basic_istream<char>'} and 'std::pair<double, double>') 20 | template<typename A> istream& operator>>(istream& os, vector<A>& a) { for(auto &c:a)os>>c; return os;} | ~~^~~ In file included from /usr/include/c++/12.2.1/fstream:38, from main.cpp:1: /usr/include/c++/12.2.1/istream:120:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(__istream_type& (*)(__istream_type&)) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' 120 | operator>>(__istream_type& (*__pf)(__istream_type&)) | ^~~~~~~~ /usr/include/c++/12.2.1/istream:120:36: note: no known conversion for argument 1 from 'std::pair<double, double>' to 'std::basic_istream<char>::__istream_type& (*)(std::basic_istream<char>::__istream_type&)' {aka 'std::basic_istream<char>& (*)(std::basic_istream<char>&)'} 120 | operator>>(__istream_type& (*__pf)(__istream_type&)) | ~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~ /usr/include/c++/12.2.1/istream:124:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(__ios_type& (*)(__ios_type&)) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>; __ios_type = std::basic_ios<char>]' 124 | operator>>(__ios_type& (*__pf)(__ios_type&)) | ^~~~~~~~ /usr/include/c++/12.2.1/istream:124:32: note: no known conversion for argument 1 from 'std::pair<double, double>' to 'std::basic_istream<char>::__ios_type& (*)(std::basic_istream<char>::__ios_type&)' {aka 'std::basic_ios<char>& (*)(std::basic_ios<char>&)'} 124 | operator>>(__ios_type& (*__pf)(__ios_type&)) | ~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~ /usr/include/c++/12.2.1/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>; __istream_type = std::basic_istream<char>]' 131 | operator>>(ios_base& (*__pf)(ios_base&)) | ^~~~~~~~ /usr/include/c++/12.2.1/istream:131:30: note: no known conversion for argument 1 from 'std::pair<double, double>' to 'std::ios_base& (*)(std::ios_base&)' 131 | operator>>(ios_base& (*__pf)(ios_base&)) | ~~~~~~~~~~~~^~~~~~~~~~~~~~~~ /usr/include/c++/12.2.1/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>; __istream_type = std::basic_istream<char>]' 168 | operator>>(bool& __n) | ^~~~~~~~ /usr/include/c++/12.2.1/istream:168:24: note: no known conversion for argument 1 from 'std::pair<double, double>' to 'bool&' 168 | operator>>(bool& __n) | ~~~~~~^~~ /usr/include/c++/12.2.1/istream:172:7: note: candidate: 'std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(short int&) [with _CharT = char; _Traits = std::char_traits<char>]' 172 | operator>>(short& __n); | ^~~~~~~~ /usr/include/c++/12.2.1/istream:172:25: note: no known conversion for argument 1 from 'std::pair<double, double>' to 'short int&' 172 | operator>>(short& __n); | ~~~~~~~^~~ /usr/include/c++/12.2.1/istream:175:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(short unsigned int&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' 175 | operator>>(unsigned short& __n) | ^~~~~~~~ /usr/include/c++/12.2.1/istream:175:34: note: no known conversion for argument 1 from 'std::pair<double, double>' to 'short unsigned int&' 175 | operator>>(unsigned short& __n) | ~~~~~~~~~~~~~~~~^~~ /usr/include/c++/12.2.1/istream:179:7: note: candidate: 'std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(int&) [with _CharT = char; _Traits = std::char_traits<char>]' 179 | operator>>(int& __n); | ^~~~~~~~ /usr/include/c++/12.2.1/istream:179:23: note: no known conversion for argument 1 from 'std::pair<double, double>' to 'int&' Non zero exit status: 1