Eroare de compilare: main.cpp: In function 'void back(int, int, int)': main.cpp:15:53: error: no match for 'operator>>' (operand types are 'std::basic_ostream<char>' and 'const char [2]') for(int i = 1; i <= K; i++) fout << comb[i] >> " "; ~~~~~~~~~~~~~~~~^~~~~~ In file included from /usr/include/c++/6/string:53:0, from /usr/include/c++/6/bits/locale_classes.h:40, from /usr/include/c++/6/bits/ios_base.h:41, from /usr/include/c++/6/ios:42, from /usr/include/c++/6/ostream:38, from /usr/include/c++/6/iostream:39, from main.cpp:1: /usr/include/c++/6/bits/basic_string.tcc:1437:5: note: candidate: template<class _CharT, class _Traits, class _Alloc> std::basic_istream<_CharT, _Traits>& std::operator>>(std::basic_istream<_CharT, _Traits>&, std::__cxx11::basic_string<_CharT, _Traits, _Alloc>&) operator>>(basic_istream<_CharT, _Traits>& __in, ^~~~~~~~ /usr/include/c++/6/bits/basic_string.tcc:1437:5: note: template argument deduction/substitution failed: main.cpp:15:56: note: 'std::basic_ostream<char>' is not derived from 'std::basic_istream<_CharT, _Traits>' for(int i = 1; i <= K; i++) fout << comb[i] >> " "; ^~~ In file included from /usr/include/c++/6/istream:934:0, from /usr/include/c++/6/iostream:40, from main.cpp:1: /usr/include/c++/6/bits/istream.tcc:963:5: note: candidate: template<class _CharT2, class _Traits2> std::basic_istream<_CharT, _Traits>& std::operator>>(std::basic_istream<_CharT, _Traits>&, _CharT2*) operator>>(basic_istream<_CharT, _Traits>& __in, _CharT* __s) ^~~~~~~~ /usr/include/c++/6/bits/istream.tcc:963:5: note: template argument deduction/substitution failed: main.cpp:15:56: note: 'std::basic_ostream<char>' is not derived from 'std::basic_istream<_CharT, _Traits>' for(int i = 1; i <= K; i++) fout << comb[i] >> " "; ^~~ In file included from /usr/include/c++/6/istream:934:0, from /usr/include/c++/6/iostream:40, from main.cpp:1: /usr/include/c++/6/bits/istream.tcc:931:5: note: candidate: template<class _CharT, class _Traits> std::basic_istream<_CharT, _Traits>& std::operator>>(std::basic_istream<_CharT, _Traits>&, _CharT&) operator>>(basic_istream<_CharT, _Traits>& __in, _CharT& __c) ^~~~~~~~ /usr/include/c++/6/bits/istream.tcc:931:5: note: template argument deduction/substitution failed: main.cpp:15:56: note: 'std::basic_ostream<char>' is not derived from 'std::basic_istream<_CharT, _Traits>' for(int i = 1; i <= K; i++) fout << comb[i] >> " "; ^~~ In file included from /usr/include/c++/6/iostream:40:0, from main.cpp:1: /usr/include/c++/6/istream:756:5: note: candidate: template<class _Traits> std::basic_istream<char, _Traits>& std::operator>>(std::basic_istream<char, _Traits>&, unsigned char&) operator>>(basic_istream<char, _Traits>& __in, unsigned char& __c) ^~~~~~~~ /usr/include/c++/6/istream:756:5: note: template argument deduction/substitution failed: main.cpp:15:56: note: 'std::basic_ostream<char>' is not derived from 'std::basic_istream<char, _Traits>' for(int i = 1; i <= K; i++) fout << comb[i] >> " "; ^~~ In file included from /usr/include/c++/6/iostream:40:0, from main.cpp:1: /usr/include/c++/6/istream:761:5: note: candidate: template<class _Traits> std::basic_istream<char, _Traits>& std::operator>>(std::basic_istream<char, _Traits>&, signed char&) Non zero exit status: 1