We have some permutation A of [0, 1, ..., N - 1], where
N is the length of A.
The number of (global) inversions is the number of i < j with 0 <= i
< j < N and A[i] > A[j].
The number of local inversions is the number of i with 0 <= i <
N and A[i] > A[i+1].
Return true if and only if the number of global inversions is equal to the
number of local inversions.
Example 1:
Input: A = [1,0,2] Output: true Explanation: There is 1 global inversion, and 1 local inversion.
Example 2:
Input: A = [1,2,0] Output: false Explanation: There are 2 global inversions, and 1 local inversion.
Note:
A will be a permutation of [0, 1, ..., A.length - 1].A will have length in range [1, 5000].