Eroare de compilare: user.cpp:16:35: error: ISO C++ forbids declaration of ‘operator+=’ with no type [-fpermissive] operator += (const number &oth) { ^ user.cpp: In member function ‘int number::operator+=(const number&)’: user.cpp:30:5: warning: no return statement in function returning non-void [-Wreturn-type] } ^ user.cpp: In function ‘int main()’: user.cpp:38:38: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d%d%d", &n, &d, &k); ^