Largest Time for Given Digits
Given an array arr of 4 digits, find the latest 24-hour time that can be made using each digit exactly once.
24-hour times are formatted as "HH:MM", where HH is between 00 and 23, and MM is between 00 and 59. The earliest 24-hour time is 00:00, and the latest is 23:59.
Return the latest 24-hour time in "HH:MM" format. If no valid time can be made, return an empty string.
Example 1
Input
arr = [1,2,3,4]Output
"23:41"The valid 24-hour times are "12:34", "12:43", "13:24", "13:42", "14:23", "14:32", "21:34", "21:43", "23:14", and "23:41"; of these times, "23:41" is the latest.
Example 2
Input
arr = [5,5,5,5]Output
""There are no valid 24-hour times as "55:55" is not valid.
Constraints
- arr.length == 4
- 0 <= arr[i] <= 9