21249번 - Not the Longest Increasing Subsequence 스페셜 저지다국어

There is an array of $n$ integers. Each element $a_i$ in this array is between $1$ and $k$.

What is the smallest number of elements that should be removed from this array, so that its longest increasing subsequence has length smaller than $k$?

The first line contains two integers $n$ and $k$ ($1 \le n \le 10^6, 1 \le k \le n$) --- the length of the array and the upper bound for its elements.

The second line contains $n$ integers $a_i$ ($1 \le a_i \le k$) --- the elements of the array.

In the first line output an integer $m$ --- the number of elements to remove.

In the second line output $m$ integers --- the indices of the removed elements. The indices are numbered from $1$ to $n$.