Eroare de compilare: user.cpp:1:21: error: fstream.h: No such file or directory user.cpp: In function ‘int main()’: user.cpp:9: error: ‘ifstream’ was not declared in this scope user.cpp:9: error: expected ‘;’ before ‘f’ user.cpp:10: error: ‘ofstream’ was not declared in this scope user.cpp:10: error: expected ‘;’ before ‘g’ user.cpp:11: error: ‘f’ was not declared in this scope user.cpp:17: error: ‘abs’ was not declared in this scope user.cpp:27: error: ‘abs’ was not declared in this scope user.cpp:36: error: ‘g’ was not declared in this scope