Codeforces Round 310 (Div. 2)
B
Case of Fake Numbers
Codeforces
1100
原题
← AC →
翻译中…

Andrewid the Android is a galaxy-famous detective. He is now investigating a case of frauds who make fake copies of the famous Stolp's gears, puzzles that are as famous as the Rubik's cube once was.

翻译中…

Its most important components are a button and a line of $*n*$ similar gears. Each gear has $*n*$ teeth containing all numbers from $0$ to $*n* - 1$ in the counter-clockwise order. When you push a button, the first gear rotates clockwise, then the second gear rotates counter-clockwise, the the third gear rotates clockwise an so on.

翻译中…

Besides, each gear has exactly one active tooth. When a gear turns, a new active tooth is the one following after the current active tooth according to the direction of the rotation. For example, if $*n* = 5$, and the active tooth is the one containing number $0$, then clockwise rotation makes the tooth with number $1$ active, or the counter-clockwise rotating makes the tooth number $4$ active.

翻译中…

Andrewid remembers that the real puzzle has the following property: you can push the button multiple times in such a way that in the end the numbers on the active teeth of the gears from first to last form sequence $0, 1, 2, ..., *n* - 1$. Write a program that determines whether the given puzzle is real or fake.

翻译中…

Input

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The first line contains integer $*n*$ ($1 ≤ *n* ≤ 1000$) — the number of gears.

翻译中…

The second line contains $*n*$ digits $*a*_{1}, *a*_{2}, ..., *a*_{*n*}$ ($0 ≤ *a*_{*i*} ≤ *n* - 1$) — the sequence of active teeth: the active tooth of the $*i*$-th gear contains number $*a*_{*i*}$.

翻译中…

Output

翻译中…

In a single line print "Yes" (without the quotes), if the given Stolp's gears puzzle is real, and "No" (without the quotes) otherwise.

翻译中…

Note

翻译中…

In the first sample test when you push the button for the first time, the sequence of active teeth will be 2 2 1, when you push it for the second time, you get 0 1 2.

翻译中…

样例

Input #1
3
1 0 0
Output #1
Yes
InputCopy OutputCopy
Input #2
5
4 2 1 4 3
Output #2
Yes
InputCopy OutputCopy
Input #3
4
0 2 3 1
Output #3
No
InputCopy OutputCopy
题目信息
题号
556B
时间限制
2 s
内存限制
256 MB
标签
暴力
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。