Question

Here is a implementation that I wrote to add hrs, min and sec in C++
Is there a way to implement this by converting all this to seconds and do a simpler implementation?
For some reason it wouldn’t let me add the code in this post 🙁

Thank you

Answer 1

Is there a way to implement this by converting all this to seconds and do a simpler implementation?

Whichever way you go, you’ll need to change the time between seconds and hour/minute/second quite often, so there’s not necessarily a huge benefit to using one or the other for storage. Put another way, seconds-since-midnight is probably nicer, but maybe not worth a rewrite. For things like + and -, if you’re not storing just seconds then you can calculate it easily (see Mark’s post), do your arithmetic then have a function to convert from seconds back to hour/min/sec to store the result into your data members:

hours = seconds_since_midnight / 60 / 60;
minutes = seconds_since_midnight / 60 % 60;
seconds = seconds_since_midnight % 60;

Say you’re adding 120 seconds to 23:59:00, you’ll get a value past midnight, so you can use “total_seconds % 24 * 60 * 60” to get just the 60 seconds past the following midnight, equivalent to wrapping from “24:01:00” to 00:01:00.

(If you want to actually use this, and not just doing this to teach yourself, then consider using the time() function and associated conversion routines like localtime())