top of page
Search

# Check if Array Is Sorted and Rotated

Updated: Mar 25, 2021

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.

```

Example 4:

```Input: nums = [1,1,1]
Output: true
Explanation: [1,1,1] is the original sorted array.
You can rotate any number of positions to make nums.

```

Example 5:

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

```

Constraints:

• 1 <= nums.length <= 100

• 1 <= nums[i] <= 100

Solution:

```class Solution {
public boolean check(int[] nums) {
int count =0;
for(int i=0;i<nums.length;i++)
{
if(nums[i]>nums[(i+1)%nums.length])
count++;
}

if(count>1) return false;
return true;
}
}```