Eroare de compilare: user.cpp:2: error: expected nested-name-specifier before ‘namespaces’ user.cpp:2: error: ‘namespaces’ has not been declared user.cpp:2: error: expected ‘;’ before ‘std’ user.cpp:2: error: expected constructor, destructor, or type conversion before ‘;’ token user.cpp: In function ‘int main()’: user.cpp:5: error: ‘fstream’ was not declared in this scope user.cpp:5: error: expected ‘;’ before ‘f’ user.cpp:7: error: ‘f’ was not declared in this scope user.cpp:8: error: ‘g’ was not declared in this scope