Method isIdealPermutation

Array/GlobalAndLocalInversions.py:36–54

:type A: List[int] :rtype: bool

(self, A)

class Solution(object):
    def isIdealPermutation(self, A):
        """
        :type A: List[int]
        :rtype: bool
        """
        global_inversions = []
        _g = 0
        
        for i in A[::-1]:
            _g += bisect.bisect_left(global_inversions, i)
            bisect.insort_left(global_inversions, i)
        
        _l = 0
        
        for i in range(len(A)-1):
            if A[i] > A[i+1]:
                _l += 1

        return _g == _l