100 years have passed since the last victory of the man versus computer in Go. Technologies made a huge step forward and robots conquered the Earth! It's time for the final fight between human and robot that will decide the faith of the planet.
The following game was chosen for the fights: initially there is a polynomial
$*P*(*x*) = *a*_{*n*}*x*^{*n*} + *a*_{*n* - 1}*x*^{*n* - 1} + ... + *a*_{1}*x* + *a*_{0},$
with yet undefined coefficients and the integer
k
. Players alternate their turns. At each turn, a player pick some index
j
, such that coefficient
aj
that stay near
xj
is not determined yet and sets it to
any
value (integer or real, positive or negative,
0
is also allowed). Computer moves first. The human will be declared the winner if and only if the resulting polynomial will be divisible by
Q(x) = x - k
.
Polynomial $*P*(*x*)$ is said to be divisible by polynomial $*Q*(*x*)$ if there exists a representation $*P*(*x*) = *B*(*x*)*Q*(*x*)$, where $*B*(*x*)$ is also some polynomial.
Some moves have been made already and now you wonder, is it true that human can guarantee the victory if he plays optimally?
Input
The first line of the input contains two integers $*n*$ and $*k*$ ($1 ≤ *n* ≤ 100 000, |*k*| ≤ 10 000$) — the size of the polynomial and the integer $*k*$.
The $*i*$-th of the following $*n* + 1$ lines contain character '?' if the coefficient near $*x*^{*i* - 1}$ is yet undefined or the integer value $*a*_{*i*}$, if the coefficient is already known ($- 10 000 ≤ *a*_{*i*} ≤ 10 000$). Each of integers $*a*_{*i*}$ (and even $*a*_{*n*}$) may be equal to $0$.
Please note, that it's not guaranteed that you are given the position of the game where it's computer's turn to move.
Output
Print "Yes" (without quotes) if the human has winning strategy, or "No" (without quotes) otherwise.
Note
In the first sample, computer set $*a*_{0}$ to $- 1$ on the first move, so if human can set coefficient $*a*_{1}$ to $0.5$ and win.
In the second sample, all coefficients are already set and the resulting polynomial is divisible by $*x* - 100$, so the human has won.
样例
1 2
-1
?
Yes
2 100
-10000
0
1
Yes
4 5
?
1
?
1
?
No
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。