I have no idea about the lab task and the details therein but this might help you:
"In all versions of UNIX, the time() system call may be used to obtain the
time of day. This call is peculiar in that if given the address of a long
integer as an argument, it places the time in that integer and returns it.
If, however, a null pointer is passed, the time of day is just returned.
Several routines are available to convert the long integer returned by time()
into an ASCII date string. With the UNIX operating system, an ASCII date
string is a string as shown below:"
So I am guessing a time function, you might be using, returns a long long integer. and given is the way to correctly display a long long integer.