Limak is a little polar bear. He doesn't have many toys and thus he often plays with polynomials.
He considers a polynomial valid if its degree is $*n*$ and its coefficients are integers not exceeding $*k*$ by the absolute value. More formally:
Let $*a*_{0}, *a*_{1}, ..., *a*_{*n*}$ denote the coefficients, so
. Then, a polynomial $*P*(*x*)$ is valid if all the following conditions are satisfied:
$*a*_{*i*}$is integer for every$*i*$;$|*a*_{*i*}| ≤ *k*$for every$*i*$;$*a*_{*n*} ≠ 0$.
Limak has recently got a valid polynomial $*P*$ with coefficients $*a*_{0}, *a*_{1}, *a*_{2}, ..., *a*_{*n*}$. He noticed that $*P*(2) ≠ 0$ and he wants to change it. He is going to change one coefficient to get a valid polynomial $*Q*$ of degree $*n*$ that $*Q*(2) = 0$. Count the number of ways to do so. You should count two ways as a distinct if coefficients of target polynoms differ.
Input
The first line contains two integers $*n*$ and $*k*$ ($1 ≤ *n* ≤ 200 000, 1 ≤ *k* ≤ 10^{9}$) — the degree of the polynomial and the limit for absolute values of coefficients.
The second line contains $*n* + 1$ integers $*a*_{0}, *a*_{1}, ..., *a*_{*n*}$ ($|*a*_{*i*}| ≤ *k*, *a*_{*n*} ≠ 0$) — describing a valid polynomial
. It's guaranteed that $*P*(2) ≠ 0$.
Output
Print the number of ways to change one coefficient to get a valid polynomial $*Q*$ that $*Q*(2) = 0$.
Note
In the first sample, we are given a polynomial $*P*(*x*) = 10 - 9*x* - 3*x*^{2} + 5*x*^{3}$.
Limak can change one coefficient in three ways:
- He can set
$*a*_{0} = - 10$. Then he would get$*Q*(*x*) = - 10 - 9*x* - 3*x*^{2} + 5*x*^{3}$and indeed$*Q*(2) = - 10 - 18 - 12 + 40 = 0$. - Or he can set
$*a*_{2} = - 8$. Then$*Q*(*x*) = 10 - 9*x* - 8*x*^{2} + 5*x*^{3}$and indeed$*Q*(2) = 10 - 18 - 32 + 40 = 0$. - Or he can set
$*a*_{1} = - 19$. Then$*Q*(*x*) = 10 - 19*x* - 3*x*^{2} + 5*x*^{3}$and indeed$*Q*(2) = 10 - 38 - 12 + 40 = 0$.
In the second sample, we are given the same polynomial. This time though, $*k*$ is equal to $12$ instead of $10^{9}$. Two first of ways listed above are still valid but in the third way we would get $|*a*_{1}| > *k*$ what is not allowed. Thus, the answer is $2$ this time.
样例
3 1000000000
10 -9 -3 5
3
3 12
10 -9 -3 5
2
2 20
14 -7 19
0
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