UnsortedSequence | Topcoder Archive

Problem Statement

We say that the sequence of numbers {s[0], s[1], s[2], ..., s[N-1]} is sorted in ascending order if we have s[i] <= s[i+1] for each i between 0 and N-2, inclusive.

For example, the sequences {1,2,3}, {1,1,1}, and {2,2,4,4,6,6} are sorted in ascending order, but the sequences {1,2,1}, {7,4,6}, and {3,2,1} are not.

You are given the sequence of numbers as a int[] s. Your task is to order the elements of this sequence into a sequence that will NOT be sorted in ascending order. Find and return the lexicographically smallest sequence we can obtain. If there is no possibility to get a sequence that is not sorted in ascending order, return an empty int[] instead.

Definition

Class:: UnsortedSequence
Method:: getUnsorted
Parameters:: int[]
Returns:: int[]
Method signature:: int[] getUnsorted(int[] s)
(be sure your method is public)

Notes

Sequence of numbers A is lexicographically smaller than B if A contains a smaller number on the first position on which they differ.
The sequence s may contain duplicates.
Note that the sequence consisting of only one element is always sorted.

Constraints

s will contain between 1 and 50 elements, inclusive.
Each element of s will be between 1 and 1000, inclusive.

Examples

```
{1,2}
```
```
Returns: {2, 1 }
```
There is only one possible sequence that is not in ascending order: {2,1}.
```
{1,2,3}
```
```
Returns: {1, 3, 2 }
```
Out of all six possible sequences, five are not in ascending order. Here they are, in lexicographic order: {1,3,2} {2,1,3} {2,3,1} {3,1,2} {3,2,1}
```
{7,2,2}
```
```
Returns: {2, 7, 2 }
```
Remember, that the given sequence may contain duplicates.
```
{1000}
```
```
Returns: { }
```
As mentioned in the Notes section, the sequence consisting of only one element is always sorted. So there is no possibility to unsort this sequence.
```
{1,1}
```
```
Returns: { }
```
There are also some longer sequences that cannot be unsorted.
```
{1,2,4,3}
```
```
Returns: {1, 2, 4, 3 }
```

{2,8,5,1,10,5,9,9,3,10,5,6,6,2,8,2,10}

Returns: {1, 2, 2, 2, 3, 5, 5, 5, 6, 6, 8, 8, 9, 10, 9, 10, 10 }

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