Check if Array is Sorted and Rotated

Problem

Given an array nums, return true if the array was originally sorted in non-decreasing order, then rotated some number of positions (including zero). Otherwise, return false.

There may be duplicates in the original array.

Note: An array A rotated by x positions results in an array B of the same length such that A[i] == B[(i+x) % A.length], where % is the modulo operation.

Example 1:

Input: nums = [3,4,5,1,2]
Output: true
Explanation: [1,2,3,4,5] is the original sorted array.
You can rotate the array by x = 3 positions to begin on the the element of value 3: [3,4,5,1,2].

Example 2:

Input: nums = [2,1,3,4]
Output: false
Explanation: There is no sorted array once rotated that can make nums.

Example 3:

Input: nums = [1,2,3]
Output: true
Explanation: [1,2,3] is the original sorted array.
You can rotate the array by x = 0 positions (i.e. no rotation) to make nums.

Constraints:

  • 1 <= nums.length <= 100
  • 1 <= nums[i] <= 100

Solution

class Solution {
    public boolean check(int[] nums) {
        var breaks = 0;

        if (nums[0] < nums[nums.length - 1]) {
            breaks += 1;
        }

        for (int i = 1; i < nums.length; i++) {
            if (nums[i] < nums[i - 1]) {
                breaks += 1;
            }
            if (breaks > 1) {
                return false;
            }
        }

        return true;
    }
}

Recent posts from blogs that I like

The artist who died alongside Scott

A physician, zoologist and ornithologist, and talented painted, he was in Antarctic in 1902-03, then returned in 1910-12, when he died trying to return from the South Pole.

via The Eclectic Light Company

Don't diagnose your opponents

When you disagree with someone, there are two paths forward. The first is to try to engage with what they’re saying: what their reasons are, whether their position is true, what evidence could be brought to bear, and so on. The second is to diagnose them: to engage with the second-order question of ...

via Sean Goedecke

FBI Arrests Executive at Ransomware Negotiation Firm

Agents with the Federal Bureau of Investigation (FBI) on Thursday arrested the co-founder of a Canadian cybersecurity firm in connection with an investigation into the ShinyHunters hacking group that recently relieved the FBI of sensitive data on thousands of agents, multiple sources tell KrebsOnSec...

via Krebs on Security