Codeforces Round 733 (Div. 1 + Div. 2, based on VK Cup 2021 - Elimination (Engine))
B
Putting Plates
Codeforces
800
原题
← AC →
翻译中…

To celebrate your birthday you have prepared a festive table! Now you want to seat as many guests as possible.

翻译中…

The table can be represented as a rectangle with height $h$ and width $w$, divided into $h \times w$ cells. Let $(i, j)$ denote the cell in the $i$-th row and the $j$-th column of the rectangle ($1 \le i \le h$; $1 \le j \le w$).

翻译中…

Into each cell of the table you can either put a plate or keep it empty.

翻译中…

As each guest has to be seated next to their plate, you can only put plates on the edge of the table — into the first or the last row of the rectangle, or into the first or the last column. Formally, for each cell $(i, j)$ you put a plate into, at least one of the following conditions must be satisfied: $i = 1$, $i = h$, $j = 1$, $j = w$.

翻译中…

To make the guests comfortable, no two plates must be put into cells that have a common side or corner. In other words, if cell $(i, j)$ contains a plate, you can't put plates into cells $(i - 1, j)$, $(i, j - 1)$, $(i + 1, j)$, $(i, j + 1)$, $(i - 1, j - 1)$, $(i - 1, j + 1)$, $(i + 1, j - 1)$, $(i + 1, j + 1)$.

翻译中…

Put as many plates on the table as possible without violating the rules above.

翻译中…

Input

翻译中…

The first line contains a single integer $t$ ($1 \le t \le 100$) — the number of test cases.

翻译中…

Each of the following $t$ lines describes one test case and contains two integers $h$ and $w$ ($3 \le h, w \le 20$) — the height and the width of the table.

翻译中…

Output

翻译中…

For each test case, print $h$ lines containing $w$ characters each. Character $j$ in line $i$ must be equal to $1$ if you are putting a plate into cell $(i, j)$, and $0$ otherwise. If there are multiple answers, print any.

翻译中…

All plates must be put on the edge of the table. No two plates can be put into cells that have a common side or corner. The number of plates put on the table under these conditions must be as large as possible.

翻译中…

You are allowed to print additional empty lines.

翻译中…

Note

翻译中…

For the first test case, example output contains the only way to put $6$ plates on the table.

翻译中…

For the second test case, there are many ways to put $4$ plates on the table, example output contains one of them.

翻译中…

Putting more than $6$ plates in the first test case or more than $4$ plates in the second test case is impossible.

翻译中…

样例

Input #1
3
3 5
4 4
5 6
Output #1
10101
00000
10101

0100
0001
1000
0010

010101
000000
100001
000000
101010
InputCopy OutputCopy
题目信息
题号
1530B
时间限制
2 s
内存限制
512 MB
标签
构造
模拟

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。