How hard is LeetCode 2855. Minimum Right Shifts to Sort the Array?

LeetCode 2855. Minimum Right Shifts to Sort the Array is rated Easy on LeetCode.

What is the time complexity of LeetCode 2855. Minimum Right Shifts to Sort the Array?

The Python solution on this page runs in O(n).

What is the space complexity of LeetCode 2855. Minimum Right Shifts to Sort the Array?

The Python solution on this page uses O(1) auxiliary space.

What topics does LeetCode 2855. Minimum Right Shifts to Sort the Array cover?

LeetCode 2855. Minimum Right Shifts to Sort the Array is tagged Array on LeetCode.

Minimum Right Shifts to Sort the Array — LeetCode 2855 Python Solution

EasyArray

Problem: #2855
Reading time: 2 min
Source: leetcode.com

The problem

You are given a 0-indexed array nums of length n containing distinct positive integers. Return the minimum number of right shifts required to sort nums and -1 if this is not possible.

Example

Input: nums = [3,4,5,1,2]
Output: 2
Explanation: After the first right shift, nums = [2,3,4,5,1].

Python solution

Python

class Solution:
    def minimumRightShifts(self, nums: List[int]) -> int:
        n = len(nums)
        i = 1
        while i < n and nums[i - 1] < nums[i]:
            i += 1
        k = i + 1
        while k < n and nums[k - 1] < nums[k] < nums[0]:
            k += 1
        return -1 if k < n else n - i

Complexity

Measure	Complexity
Time	O(n)
Space	O(1) auxiliary

Frequently asked questions

How hard is LeetCode 2855. Minimum Right Shifts to Sort the Array?: LeetCode 2855. Minimum Right Shifts to Sort the Array is rated Easy on LeetCode.
What is the time complexity of LeetCode 2855. Minimum Right Shifts to Sort the Array?: The Python solution on this page runs in O(n).
What is the space complexity of LeetCode 2855. Minimum Right Shifts to Sort the Array?: The Python solution on this page uses O(1) auxiliary space.
What topics does LeetCode 2855. Minimum Right Shifts to Sort the Array cover?: LeetCode 2855. Minimum Right Shifts to Sort the Array is tagged Array on LeetCode.