Eroare de compilare: user.cpp: In function ‘int main()’: user.cpp:99:21: error: cannot pass objects of non-trivially-copyable type ‘std::string {aka class std::basic_string<char>}’ through ‘...’ printf("%s\n",sol); ^ user.cpp:99:21: warning: format ‘%s’ expects argument of type ‘char*’, but argument 2 has type ‘std::string {aka std::basic_string<char>}’ [-Wformat=]