Minimum adjacent difference in a circular array

 Minimum adjacent difference in a circular array 

Easy Accuracy: 54.61% Submissions: 16413 Points: 2

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Given an array Arr of n integers arranged in a circular fashion. Your task is to find the minimum absolute difference between adjacent elements.

Example 1:

Input:
n = 7
Arr[] = {8,-8,9,-9,10,-11,12}
Output: 4
Explanation: The absolute difference 
between adjacent elements in the given 
array are as such: 16 17 18  19 21 23 4
(first and last). Among the calculated 
absolute difference the minimum is 4.

Example 2:

Input:
n = 8
Arr[] = {10,-3,-4,7,6,5,-4,-1}
Output: 1
Explanation: The absolute difference 
between adjacent elements in the given 
array are as such: 13 1 11 1 1 9 3 11
(first and last).  Among the calculated 
absolute difference, the minimum is 1.

Your Task:
The task is to complete the function minAdjDiff() which returns the minimum difference between adjacent elements in circular array.

Expected Time Complexity: O(n).
Expected Auxiliary Space: O(1).

Constraint:
2 <= n <= 106
-106 <= Arr[i] <= 106

Solution

// { Driver Code Starts

#include <bits/stdc++.h>

using namespace std;

 // } Driver Code Ends

class Solution{

    public:

    //Function to find minimum adjacent difference in a circular array.

    // arr[]: input array

    // n: size of array

    int minAdjDiff(int arr[], int n){    

        // Your code here

        int abs_diff = abs(arr[n-1]-arr[0]);

        for(int i=1;i<n;i++)

            abs_diff = min(abs(arr[i]-arr[i-1]),abs_diff);

        return abs_diff;

    }

};

// { Driver Code Starts.

// Driver code

int main()

{

    int t;

    cin>>t; //Input testcases

    

    while(t--) //While testcases exist

    {

        int n;

        cin>>n; //Input size of array

        

        int arr[n]; //Array of size n

        

        for(int i = 0; i < n; i++)

        {

            cin>>arr[i]; //input elements of array

        }

        Solution ob;

        

        cout << ob.minAdjDiff(arr, n) << endl;

    }

    return 0;

}  // } Driver Code Ends