Codeforces Round 580 (Div. 2)
E
Palindromic Paths
Codeforces
未评级
原题
← DF →
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This is an interactive problem

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You are given a grid $n\times n$, where $n$ is odd. Rows are enumerated from $1$ to $n$ from up to down, columns are enumerated from $1$ to $n$ from left to right. Cell, standing on the intersection of row $x$ and column $y$, is denoted by $(x, y)$.

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Every cell contains $0$ or $1$. It is known that the top-left cell contains $1$, and the bottom-right cell contains $0$.

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We want to know numbers in all cells of the grid. To do so we can ask the following questions:

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"$?$ $x_1$ $y_1$ $x_2$ $y_2$", where $1 \le x_1 \le x_2 \le n$, $1 \le y_1 \le y_2 \le n$, and $x_1 + y_1 + 2 \le x_2 + y_2$. In other words, we output two different cells $(x_1, y_1)$, $(x_2, y_2)$ of the grid such that we can get from the first to the second by moving only to the right and down, and they aren't adjacent.

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As a response to such question you will be told if there exists a path between $(x_1, y_1)$ and $(x_2, y_2)$, going only to the right or down, numbers in cells of which form a palindrome.

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For example, paths, shown in green, are palindromic, so answer for "$?$ $1$ $1$ $2$ $3$" and "$?$ $1$ $2$ $3$ $3$" would be that there exists such path. However, there is no palindromic path between $(1, 1)$ and $(3, 1)$.

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image

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Determine all cells of the grid by asking not more than $n^2$ questions. It can be shown that the answer always exists.

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Input

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The first line contains odd integer ($3 \le n \lt 50$) — the side of the grid.

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Interaction

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You begin the interaction by reading $n$.

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To ask a question about cells $(x_1, y_1), (x_2, y_2)$, in a separate line output "$?$ $x_1$ $y_1$ $x_2$ $y_2$".

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Numbers in the query have to satisfy $1 \le x_1 \le x_2 \le n$, $1 \le y_1 \le y_2 \le n$, and $x_1 + y_1 + 2 \le x_2 + y_2$. Don't forget to 'flush', to get the answer.

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In response, you will receive $1$, if there exists a path going from $(x_1, y_1)$ to $(x_2, y_2)$ only to the right or down, numbers in cells of which form a palindrome, and $0$ otherwise.

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In case your query is invalid or you asked more than $n^2$ queries, program will print $-1$ and will finish interaction. You will receive Wrong answer verdict. Make sure to exit immediately to avoid getting other verdicts.

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When you determine numbers in all cells, output "!".

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Then output $n$ lines, the $i$-th of which is a string of length $n$, corresponding to numbers in the $i$-th row of the grid.

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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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Hack Format

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To hack, use the following format.

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The first line should contain a single odd integer $n$ (side of your grid).

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The $i$-th of $n$ following lines should contain a string of length $n$ corresponding to the $i$-th row of the grid. Top left element of the grid has to be equal to $1$, bottom right has to be equal to $0$.

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样例

Input #1
3
0
1
0
1
1
1
1
Output #1
? 1 1 1 3
? 1 1 2 3
? 2 1 2 3
? 3 1 3 3
? 2 2 3 3
? 1 2 3 2
? 1 2 3 3
!
100
001
000
InputCopy OutputCopy
题目信息
题号
1206E
时间限制
1 s
内存限制
256 MB

题面与样例版权归 Codeforces 及出题人所有;中文翻译由 AI 生成(CI 管线),如有出入请以原文为准。