Main.cc: In function ‘int main()’: Main.cc:5:7: error: no matching function for call to ‘get(char [105])’ get(a); ^ In file included from /usr/include/c++/7/algorithm:60:0, from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:65, from Main.cc:1: /usr/include/c++/7/utility:225:5: note: candidate: template constexpr typename std::tuple_element<_Int, std::pair<_Tp1, _Tp2> >::type& std::get(std::pair<_Tp1, _Tp2>&) get(std::pair<_Tp1, _Tp2>& __in) noexcept ^~~ /usr/include/c++/7/utility:225:5: note: template argument deduction/substitution failed: Main.cc:5:7: note: mismatched types ‘std::pair<_Tp1, _Tp2>’ and ‘char [105]’ get(a); ^ In file included from /usr/include/c++/7/algorithm:60:0, from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:65, from Main.cc:1: /usr/include/c++/7/utility:230:5: note: candidate: template constexpr typename std::tuple_element<_Int, std::pair<_Tp1, _Tp2> >::type&& std::get(std::pair<_Tp1, _Tp2>&&) get(std::pair<_Tp1, _Tp2>&& __in) noexcept ^~~ /usr/include/c++/7/utility:230:5: note: template argument deduction/substitution failed: Main.cc:5:7: note: mismatched types ‘std::pair<_Tp1, _Tp2>’ and ‘char [105]’ get(a); ^ In file included from /usr/include/c++/7/algorithm:60:0, from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:65, from Main.cc:1: /usr/include/c++/7/utility:235:5: note: candidate: template constexpr const typename std::tuple_element<_Int, std::pair<_Tp1, _Tp2> >::type& std::get(const std::pair<_Tp1, _Tp2>&) get(const std::pair<_Tp1, _Tp2>& __in) noexcept ^~~ /usr/include/c++/7/utility:235:5: note: template argument deduction/substitution failed: Main.cc:5:7: note: mismatched types ‘const std::pair<_Tp1, _Tp2>’ and ‘char [105]’ get(a); ^ In file included from /usr/include/c++/7/tuple:39:0, from /usr/include/c++/7/functional:54, from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:71, from Main.cc:1: /usr/include/c++/7/array:307:5: note: candidate: template constexpr _Tp& std::get(std::array<_Tp, _Nm>&) get(array<_Tp, _Nm>& __arr) noexcept ^~~ /usr/include/c++/7/array:307:5: note: template argument deduction/substitution failed: Main.cc:5:7: note: mismatched types ‘std::array<_Tp, _Nm>’ and ‘char [105]’ get(a); ^ In file included from /usr/include/c++/7/tuple:39:0, from /usr/include/c++/7/functional:54, from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:71, from Main.cc:1: /usr/include/c++/7/array:316:5: note: candidate: template constexpr _Tp&& std::get(std::array<_Tp, _Nm>&&) get(array<_Tp, _Nm>&& __arr) noexcept ^~~ /usr/include/c++/7/array:316:5: note: template argument deduction/substitution failed: Main.cc:5:7: note: mismatched types ‘std::array<_Tp, _Nm>’ and ‘char [105]’ get(a); ^ In file included from /usr/include/c++/7/tuple:39:0, from /usr/include/c++/7/functional:54, from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:71, from Main.cc:1: /usr/include/c++/7/array:324:5: note: candidate: template constexpr const _Tp& std::get(const std::array<_Tp, _Nm>&) get(const array<_Tp, _Nm>& __arr) noexcept ^~~ /usr/include/c++/7/array:324:5: note: template argument deduction/substitution failed: Main.cc:5:7: note: mismatched types ‘const std::array<_Tp, _Nm>’ and ‘char [105]’ get(a); ^ In file included from /usr/include/c++/7/functional:54:0, from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:71, from Main.cc:1: /usr/include/c++/7/tuple:1314:5: note: candidate: template constexpr std::__tuple_element_t<__i, std::tuple<_Elements ...> >& std::get(std::tuple<_Elements ...>&) get(tuple<_Elements...>& __t) noexcept ^~~ /usr/include/c++/7/tuple:1314:5: note: template argument deduction/substitution failed: Main.cc:5:7: note: mismatched types ‘std::tuple<_Elements ...>’ and ‘char [105]’ get(a); ^ In file included from /usr/include/c++/7/functional:54:0, from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:71, from Main.cc:1: /usr/include/c++/7/tuple:1320:5: note: candidate: template constexpr std::__tuple_element_t<__i, std::tuple<_Elements ...> >& std::get(const std::tuple<_Elements ...>&) get(const tuple<_Elements...>& __t) noexcept ^~~ /usr/include/c++/7/tuple:1320:5: note: template argument deduction/substitution failed: Main.cc:5:7: note: mismatched types ‘const std::tuple<_Elements ...>’ and ‘char [105]’ get(a); ^ In file included from /usr/include/c++/7/functional:54:0, from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:71, from Main.cc:1: /usr/include/c++/7/tuple:1326:5: note: candidate: template constexpr std::__tuple_element_t<__i, std::tuple<_Elements ...> >&& std::get(std::tuple<_Elements ...>&&) get(tuple<_Elements...>&& __t) noexcept ^~~ /usr/include/c++/7/tuple:1326:5: note: template argument deduction/substitution failed: Main.cc:5:7: note: mismatched types ‘std::tuple<_Elements ...>’ and ‘char [105]’ get(a); ^ Main.cc:6:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i