Eroare de compilare: user.cpp: In function ‘int main()’: user.cpp:16:16: error: variable ‘std::ifstream in’ has initializer but incomplete type ifstream in("fact.in"); ^ user.cpp:17:17: error: variable ‘std::ofstream out’ has initializer but incomplete type ofstream out("fact.out"); ^ user.cpp: At global scope: user.cpp:38:5: error: expected unqualified-id before ‘return’ return 0; ^ user.cpp:39:1: error: expected declaration before ‘}’ token } ^