Package g0701_0800.s0775_global_and_local_inversions

Class Solution

  • All Implemented Interfaces:
    
public final class Solution

    775 - Global and Local Inversions.

    Medium

    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.

    Constraints:

    • n == nums.length

    • <code>1 <= n <= 10<sup>5</sup></code>

    • 0 &lt;= nums[i] &lt; n

    • All the integers of nums are unique.

    • nums is a permutation of all the numbers in the range [0, n - 1].

    • Nested Class Summary

      Nested Classes 
      Modifier and Type Class Description

    • Field Summary

      Fields 
      Modifier and Type Field Description

    • Constructor Summary

      Constructors 
      Constructor Description
      Solution()

    • Enum Constant Summary

      Enum Constants 
      Enum Constant Description

    • Method Summary

      Modifier and Type Method Description
      final Boolean isIdealPermutation(IntArray nums)

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait