Unordered Subsequence

문제 정보

문제

The sequence is called ordered if it is non-decreasing (i.e. Ai <= Ai+1 for 1 <= i < N) or non-increasing (i.e. Ai >= Ai+1 for 1 <= i < N). Therefore, the sequence [1, 3, 3, 1] is not ordered.

You are given a sequence of numbers. You are to find its shortest subsequence which is not ordered. Note that subsequence does not need to be consecutive.

입력

The first line of the input contains one integer T, the number of test cases.

The first line of each test case contains one integer N (1 <= N <= 10^5).
The second line contains N space-seperated integers - the given sequence.
Absolute values of numbers in input sequences do not exceed 10^6.

출력

If the given sequence does not contain any unordered subsequences, output 0.

Otherwise, output the length K of the shortest such subsequence.
Then output K integers on the next line, representing indexes of the subsequence from the input sequence.

If there are several solutions, output the lexicographically earlist one.
Sequence A is lexicographically earlier than sequence B if Ai < Bi for the smallest index i such that Ai != Bi.

예제 입력

3
5             
67 499 600 42 23
3                        
1 2 3
3                        
2 3 1

예제 출력

3
1 2 4
0
3
1 2 3

노트

4개의 댓글이 있습니다.