Given two positive integers n , m . The task is to count the number of different array that can be formed of size n such that each element is between 1 to m and two consecutive element are different. Also, the first and last elements of each array should be same.
Print Answer of modulo of 10^9 + 7.
Expected TC: O(logn)
Contraints: 3 <= N, M <= 10^18
I/p O/p
3 3 --> 6
3 4 --> 12
4 4 --> 24