We call two numbers friendly if they have the same digits, ignoring order or repetition. For example 122213 and 312 are friendly while 145 and 2544411 are not. A sequence is friendly if it contains at least two numbers, and all possible pairs of numbers within it are friendly. Two contiguous subsequences are different if they have a different start index, end index or both.
If we are given the sequence 112, 12, 21, 354, 534345, 345, 2221 then the friendly contiguous subsequences are: {112, 12}, {112, 12, 21}, {12, 21}, {354, 534345}, {354, 534345, 345} and {534345, 345}. {112, 12, 21, 354} is not a friendly contiguous subsequence because 112 and 354 are not friendly numbers and {112, 12, 21, 2221} is not a friendly contignuous subsequence because the elements of the sequence aren't in consecutive positions in the original sequence.
Given a int[] array, you must return number of different friendly contignuous subsequences of array.
