if I print time(0)/3600/24/365 it displays 46 what does that mean?

Question

time()

Answer 1

It means that the start of Unix time was 46 years ago, in 1970.

time(0) gives you the number of seconds since the 1st January, 1970 (UTC).
Dividing by 3600 gives you the hours.
Dividing by 24 gives you the days.
Dividing by 365 gives you the years.

Answer 2

how Unix related to CPP?