Simon has a prime number $*x*$ and an array of non-negative integers $*a*_{1}, *a*_{2}, ..., *a*_{*n*}$.
Simon loves fractions very much. Today he wrote out number
on a piece of paper. After Simon led all fractions to a common denominator and summed them up, he got a fraction:
, where number $*t*$ equals $*x*^{*a*_{1} + *a*_{2} + ... + *a*_{*n*}}$. Now Simon wants to reduce the resulting fraction.
Help him, find the greatest common divisor of numbers $*s*$ and $*t*$. As GCD can be rather large, print it as a remainder after dividing it by number $1000000007$ ($10^{9} + 7$).
Input
The first line contains two positive integers $*n*$ and $*x*$ ($1 ≤ *n* ≤ 10^{5}$, $2 ≤ *x* ≤ 10^{9}$) — the size of the array and the prime number.
The second line contains $*n*$ space-separated integers $*a*_{1}, *a*_{2}, ..., *a*_{*n*}$ ($0 ≤ *a*_{1} ≤ *a*_{2} ≤ ... ≤ *a*_{*n*} ≤ 10^{9}$).
Output
Print a single number — the answer to the problem modulo $1000000007$ ($10^{9} + 7$).
Note
In the first sample
. Thus, the answer to the problem is $8$.
In the second sample,
. The answer to the problem is $27$, as $351 = 13·27$, $729 = 27·27$.
In the third sample the answer to the problem is $1073741824 *mod* 1000000007 = 73741817$.
In the fourth sample
. Thus, the answer to the problem is $1$.
样例
2 2
2 2
8
3 3
1 2 3
27
2 2
29 29
73741817
4 5
0 0 0 0
1
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