Given four digits, find the maximum valid time that can be displayed on a digital clock (in 24-hour format) using those digits. For example, given digits 1, 8, 3, 2 the maximum valid time is "23:18". Note that "28:31" is not a valid time. Write a function: string MaxTime(int A, int B, int C, int D); that, given four integers A, B, C, D, returns the maximum valid time in string format "HH:MM" or "NOT POSSIBLE" if it is not possible to display a valid time. Examples: given 1, 8, 3, 2, the function MaxTime shoud return "23:18". Given 2, 4, 0, 0 the function should return "20:40". Given 3, 0, 7, 0 the function should return "07:30" Given 9, 1, 9, 7 the function should return "NOT POSSIBLE". Since there is no possible valid time. Assume that: A, B, C, D are integers with in the range [0..9] In your solution, focus on correctness as well as the performance of your solution. Try to achieve O(n) if possible rather than O(n^2) solution. The format of a date needs to be changed in the following manner: 1 st Mar 1984 => 1984-03-01 Write a function 'ReformatDate' which will take the input String and returns the new format of the string. String ReformatDate(String oldDate); Example: 1st Mar 1984 => 1984-03-01 2nd Feb 2013 =>2013-02-02 15th Apr 1840 => 1840-04-15 The 'Day' may equal any one of the following values: 1st, 2nd, 3rd, 4th, 5th, 6th, 7th, 8th, 9th, ..... 29th, 30th, 31st The 'Month' may equal any one of the following values: Jan, Feb, Mar, Apr, May, Jun, Jul, Aug, Sep, Oct, Nov, Dec The Year will always be represented by 4 digits and may equal anything between 1900 and 2100, both inclusive. Your Task is to format the given list of dates in to the following format: YYYY-MM-DD Where: YYYY represents the year in 4 digits MM represents the year in 2 digits DD represents the day in 2 digits