long and long int are identical. So are long long and long long int. In both cases, the int is optional. As to the difference between the two sets, the C++ standard mandates minimum ranges for each, and that long long is at least as wide as long. The controlling parts of the standard (C++11, … Read more
See the reference documentation for the String class: String s = String.valueOf(date); If your Long might be null and you don’t want to get a 4-letter “null” string, you might use Objects.toString, like: String s = Objects.toString(date, null); EDIT: You reverse it using Long l = Long.valueOf(s); but in this direction you need to catch … Read more
%lu is the correct format for unsigned long. Sounds like there are other issues at play here, such as memory corruption or an uninitialized variable. Perhaps show us a larger picture?
Put an l (lowercased letter L) directly before the specifier. unsigned long n; long m; printf(“%lu %ld”, n, m);