Eroare de compilare: user.cpp:13:21: error: fstream.h: No such file or directory user.cpp: In function ‘int main()’: user.cpp:21: error: ‘ifstream’ was not declared in this scope user.cpp:21: error: expected ‘;’ before ‘in’ user.cpp:22: error: ‘ofstream’ was not declared in this scope user.cpp:22: error: expected ‘;’ before ‘out’ user.cpp:23: error: ‘in’ was not declared in this scope user.cpp:30: error: ‘out’ was not declared in this scope user.cpp:20: warning: unused variable ‘f’