The time has a format: hours:minutes. Both hours and minutes has two digits, like 09:00.

Make a regexp to find time in the string: Breakfast at 09:00 in the room 123:456.

P.S. In this task there’s no need to check time correctness yet, so 25:99 can also be a valid result.

P.P.S. The regexp shouldn’t match 123:456.