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E. So Mean
time limit per test
4 seconds
memory limit per test
256 megabytes
standard input
standard output

This problem is interactive.

We have hidden a permutation $$$p_1, p_2, \dots, p_n$$$ of numbers from $$$1$$$ to $$$n$$$ from you, where $$$n$$$ is even. You can try to guess it using the following queries:

$$$?$$$ $$$k$$$ $$$a_1$$$ $$$a_2$$$ $$$\dots$$$ $$$a_k$$$.

In response, you will learn if the average of elements with indexes $$$a_1, a_2, \dots, a_k$$$ is an integer. In other words, you will receive $$$1$$$ if $$$\frac{p_{a_1} + p_{a_2} + \dots + p_{a_k}}{k}$$$ is integer, and $$$0$$$ otherwise.

You have to guess the permutation. You can ask not more than $$$18n$$$ queries.

Note that permutations $$$[p_1, p_2, \dots, p_k]$$$ and $$$[n + 1 - p_1, n + 1 - p_2, \dots, n + 1 - p_k]$$$ are indistinguishable. Therefore, you are guaranteed that $$$p_1 \le \frac{n}{2}$$$.

Note that the permutation $$$p$$$ is fixed before the start of the interaction and doesn't depend on your queries. In other words, interactor is not adaptive.

Note that you don't have to minimize the number of queries.


The first line contains a single integer $$$n$$$ ($$$2 \le n \le 800$$$, $$$n$$$ is even).


You begin the interaction by reading $$$n$$$.

To ask a question about elements on positions $$$a_1, a_2, \dots, a_k$$$, in a separate line output

$$$?$$$ $$$k$$$ $$$a_1$$$ $$$a_2$$$ ... $$$a_k$$$

Numbers in the query have to satisfy $$$1 \le a_i \le n$$$, and all $$$a_i$$$ have to be different. Don't forget to 'flush', to get the answer.

In response, you will receive $$$1$$$ if $$$\frac{p_{a_1} + p_{a_2} + \dots + p_{a_k}}{k}$$$ is integer, and $$$0$$$ otherwise.

In case your query is invalid or you asked more than $$$18n$$$ queries, the program will print $$$-1$$$ and will finish interaction. You will receive a Wrong answer verdict. Make sure to exit immediately to avoid getting other verdicts.

When you determine permutation, output

$$$!$$$ $$$p_1$$$ $$$p_2$$$ ... $$$p_n$$$

After printing a query do not forget to output end of line and flush the output. Otherwise, you will get Idleness limit exceeded. To do this, use:

  • fflush(stdout) or cout.flush() in C++;
  • System.out.flush() in Java;
  • flush(output) in Pascal;
  • stdout.flush() in Python;
  • see documentation for other languages.

Hack format

For the hacks use the following format:

The first line has to contain a single integer $$$n$$$ ($$$2 \le n \le 800$$$, $$$n$$$ is even).

In the next line output $$$n$$$ integers $$$p_1, p_2, \dots, p_n$$$ — the valid permutation of numbers from $$$1$$$ to $$$n$$$. $$$p_1 \le \frac{n}{2}$$$ must hold.

1 2
? 1 2
? 1 1
! 1 2