Codeforces Round 669 (Div. 2)
C
Chocolate Bunny
Codeforces
1600
原题
← BD →
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This is an interactive problem.

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We hid from you a permutation $p$ of length $n$, consisting of the elements from $1$ to $n$. You want to guess it. To do that, you can give us 2 different indices $i$ and $j$, and we will reply with $p_{i} \bmod p_{j}$ (remainder of division $p_{i}$ by $p_{j}$).

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We have enough patience to answer at most $2 \cdot n$ queries, so you should fit in this constraint. Can you do it?

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As a reminder, a permutation of length $n$ is an array consisting of $n$ distinct integers from $1$ to $n$ in arbitrary order. For example, $[2,3,1,5,4]$ is a permutation, but $[1,2,2]$ is not a permutation ($2$ appears twice in the array) and $[1,3,4]$ is also not a permutation ($n=3$ but there is $4$ in the array).

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Input

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The only line of the input contains a single integer $n$ ($1 \le n \le 10^4$) — length of the permutation.

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Interaction

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The interaction starts with reading $n$.

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Then you are allowed to make at most $2 \cdot n$ queries in the following way:

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  • "? x y" ($1 \le x, y \le n, x \ne y$).
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After each one, you should read an integer $k$, that equals $p_x \bmod p_y$.

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When you have guessed the permutation, print a single line "! " (without quotes), followed by array $p$ and quit.

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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:

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  • 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.
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Exit immediately after receiving "-1" and you will see Wrong answer verdict. Otherwise you can get an arbitrary verdict because your solution will continue to read from a closed stream.

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Hack format

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In the first line output $n$ ($1 \le n \le 10^4$). In the second line print the permutation of $n$ integers $p_1, p_2, \ldots, p_n$.

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样例

Input #1
3

1

2

1

0
Output #1
? 1 2

? 3 2

? 1 3

? 2 1

! 1 3 2
InputCopy OutputCopy
题目信息
题号
1407C
时间限制
1 s
内存限制
256 MB
标签
构造
交互题
数学
双指针

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