#775
Global and Local Inversions
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Description
You are given an integer array nums of length n which represents a permutation of all the integers in the range [0, n - 1].
The number of global inversions is the number of the different pairs (i, j) where:
- 0 <= i < j < n
- nums[i] > nums[j]
The number of local inversions is the number of indices i where:
- 0 <= i < n - 1
- nums[i] > nums[i + 1]
Return true if the number of global inversions is equal to the number of local inversions.
Example 1:
Input: nums = [1,0,2]
Output: true
Explanation: There is 1 global inversion and 1 local inversion.
Example 2:
Input: nums = [1,2,0]
Output: false
Explanation: There are 2 global inversions and 1 local inversion.
Solution