In the middle of winter, djq and dxm are playing cards.
The two players first agree on two positive integers $n$ and $k$, such that $n$ is even and $n \geq 2k$. Then, each player receives $k$ cards. The $i$-th card ($1 \leq i \leq k$) in dxm's hand has the positive integer $n+(2i-1)$ written on it, and the $i$-th card in djq's hand has the positive integer $n-(2i-1)$ written on it. Note that the cards held by both players together form $2k$ consecutive odd integers.
The game consists of $k$ rounds. In each round, both players play one card from their remaining hand, and played cards cannot be retrieved. If the numbers on the two cards are coprime, djq scores one point; otherwise, dxm scores one point. After all rounds are completed, both players calculate their total scores.
djq already knows that in the $i$-th round, dxm will play the $i$-th card from his hand. Now he wants to know:
- His highest possible score;
- A strategy for playing his cards to achieve this maximum score.
Please write a program to help him!
Input
A single line containing two positive integers $n$ and $k$.
Output
The first line should output an integer $s$, representing the maximum possible score for djq.
The next $k$ lines should each output an integer, where the $i$-th line contains the integer $p_i$, representing the index of the card djq should play in the $i$-th round.
Examples
Input 1
10 3
Output 1
3
3
1
2
Note 1
dxm's cards are $[11, 13, 15]$ in order, and djq's cards are $[9, 7, 5]$ in order. djq only needs to play his cards in the order $[5, 9, 7]$ to get all $3$ points.
Implementation Details
This problem uses a Special Judge. To ensure the Special Judge works correctly, you must ensure:
- The first line of your output is an integer in $[0, k]$.
- The next $k$ lines each contain an integer in $[1, k]$.
- The output contains no other content.
Violating these specifications may result in receiving no points.
Provided the output follows the specifications, scoring is as follows:
- If both $s$ and the output strategy are correct, you receive full marks for the test case.
- If $s$ is correct but the output strategy is incorrect, you receive $15\%$ of the marks for the test case.
- Otherwise, you will receive no marks.
Constraints
For all data, $1 \leq k \leq 10^6$, $2k \leq n \leq 10^{100}$, and $n$ is guaranteed to be even.
This problem consists of several subtasks. For each subtask, your score is the minimum score among all test cases within that subtask.
| Subtask ID | $k$ | $n$ | Score |
|---|---|---|---|
| $1$ | $\leq 10$ | $\leq 10^9$ | $5$ |
| $2$ | $\leq 20$ | $5$ | |
| $3$ | $\leq 200$ | $15$ | |
| $4$ | $\leq 2 \times 10^3$ | $10$ | |
| $5$ | $n=2k$ | $25$ | |
| $6$ | $\leq 10^5$ | $\leq 10^9$ | $10$ |
| $7$ | $15$ | ||
| $8$ | $15$ |