Find the number of ways to construct a string of length n using k Latin letters (the size of the alphabet is k) in the form of the concatenation of two nonempty palindromes.

Input

Two positive integers n and k (1 ≤ n ≤ 105, 1 ≤ k ≤ 26).

Output

Print the number of ways to construct the given string. Print the answer modulo 109 + 7.

Explanation

In the first test case the string of length 4 using one letter (а for example) can be constructed in three ways: a + aaa, aa + aa, aaa + a.