#775

Global and Local Inversions

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Description

Given a length-n permutation nums of [0, n-1], a global inversion is any pair (i, j) with i < j and nums[i] > nums[j], while a local inversion is any adjacent pair (i, i+1) with nums[i] > nums[i+1]. Every local inversion is also a global inversion.

Return true if the counts of global and local inversions are equal (i.e., there are no non-adjacent global 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.

Code

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class Solution:
    def isIdealPermutation(self, nums: List[int]) -> bool:

class Solution:
    def isIdealPermutation(self, nums: List[int]) -> bool: