Find the max date and time from given set of digits in java

Question

The problem states that there are some random digits given as input and we have to find the maximum date and time in the format MM/DD HH:MM. Ex:

Input is: 2,2,3,1,3,3,3,5,6,2,0

Output is: 12/30 23:56

I tried the brute force method where each digit is combined with every other digit to form a 2 digit number and so on. But the whole program had around 8 or 9 for loops. Is there a more efficient way to do this??

Edit1: If no possible month or date or time can be formed then the output must be 0. There is no auto insertion of 0s i.e. if you want to form a month 09 then 0 has to be in input and there cannot be repetition of digits.

Answer 1

If you need a largest date, I can think of something like that (in preudocode):

Turn the input digits into a MultiSet // e.g. https://www.geeksforgeeks.org/multiset-interface-guava-java/
for i = 12 to 1 // find the biggest possible month
  try to find if the digits of i are in the multi set. if they are, init the month value & remove them from the multi set.
for d = 31 to 1 // get the biggest possible day
  same
for h = 23 to 1 // get the biggest possible hour
  same
for m = 59 to 1 // get the biggest possible minute
  same