[npgatech]

If all inputs are in hh:mm format, then there is no ambiguity of 930 as 9:30 am/pm. There could be a toggle for AM/PM.

Who puts seconds as an input for setting their morning alarm? MAD!

[dogecoinbase]

What's the unambiguous setting of 73:45 in hh:mm format?

[KozmoNau7]

3 days, 1 hour, 45 minutes. Simple.

The Android clock app silently corrects 73 minutes to 1 hour 13 minutes.

So for 1:13:45 (hh:mm:ss) you can input "7345" on the keypad and It. Just. Works.

[lobster_johnson]

But an alarm clock sets a relative point in time that happens every day. Putting "3 days" into a calendar is fine, but for an alarm clock it makes no sense.

[KozmoNau7]

So you add basic input validation.

[lobster_johnson]

Yes, but the person who originally proposed this argued that there was no ambiguity.

[oneeyedpigeon]

Invalid input, just as the empty string or a single digit would be.