Eroare de compilare: user.cpp: In function ‘int f(long long int)’: user.cpp:9:18: error: ‘int f(long long int)’ redeclared as different kind of symbol int f(long long x){ ^ user.cpp:6:10: error: previous declaration of ‘std::ifstream f’ ifstream f("fact.in"); ^ user.cpp: In function ‘int main()’: user.cpp:24:19: error: no match for call to ‘(std::ifstream {aka std::basic_ifstream<char>}) (long long int&)’ p-=f(x); ^