Minimum absolute difference of adjacent elements in a circular array

08 Jun, 2022
Given n integers, which form a circle. Find the minimal absolute value of any adjacent pair. If there are many optimum solutions, output any of them. Note: they are in circle Examples:  
Input : arr[] = {10, 12, 13, 15, 10} 
Output : 0
Explanation: |10 - 10| = 0 which is the 
minimum possible.

Input : arr[] = {10, 20, 30, 40}
Output : 10
Explanation: |10 - 20| = 10 which is the 
minimum, 2 3 or 3 4 can be the answers also.  
 
Initially consider the minimum value to be of first and second elements. Traverse from second element to last. Check the difference of every adjacent pair and store the minimum value. When last element is reached, check its difference with first element.Below is the implementation of the above approach. 
C++
Java
Python3
C#
PHP
Javascript
// C++ program to find maximum difference// between adjacent elements in a circular array.#include <bits/stdc++.h>using namespace std; void minAdjDifference(int arr[], int n){    if (n < 2)        return;     // Checking normal adjacent elements    int res = abs(arr[1] - arr[0]);    for (int i = 2; i < n; i++)        res = min(res, abs(arr[i] - arr[i - 1]));     // Checking circular link    res = min(res, abs(arr[n - 1] - arr[0]));     cout << "Min Difference = " << res;} // driver program to check the above functionint main(){    int a[] = { 10, 12, 13, 15, 10 };    int n = sizeof(a) / sizeof(a[0]);    minAdjDifference(a, n);    return 0;}
// Java program to find maximum difference// between adjacent elements in a circular// array.class GFG {     static void minAdjDifference(int arr[], int n)    {        if (n < 2)            return;         // Checking normal adjacent elements        int res = Math.abs(arr[1] - arr[0]);        for (int i = 2; i < n; i++)            res = Math.min(res, Math.abs(arr[i] - arr[i - 1]));         // Checking circular link        res = Math.min(res, Math.abs(arr[n - 1] - arr[0]));         System.out.print("Min Difference = " + res);    }     // driver code    public static void main(String arg[])    {         int a[] = { 10, 12, 13, 15, 10 };        int n = a.length;         minAdjDifference(a, n);    }} // This code is contributed by Anant Agarwal// and improved by Anuj Sharma.
# Python3 program to find maximum# difference between adjacent# elements in a circular array. def minAdjDifference(arr, n):     if (n < 2): return     # Checking normal adjacent elements    res = abs(arr[1] - arr[0])         for i in range(2, n):        res = min(res, abs(arr[i] - arr[i - 1]))     # Checking circular link    res = min(res, abs(arr[n - 1] - arr[0]))     print("Min Difference = ", res) # Driver Codea = [10, 12, 13, 15, 10]n = len(a)minAdjDifference(a, n) # This code is contributed by Anant Agarwal# and improved by Anuj Sharma.
// C# program to find maximum difference// between adjacent elements in a circular array.using System; class GFG {     static void minAdjDifference(int[] arr, int n)    {        if (n < 2)            return;         // Checking normal adjacent elements        int res = Math.Abs(arr[1] - arr[0]);        for (int i = 2; i < n; i++)            res = Math.Min(res, Math.Abs(arr[i] - arr[i - 1]));         // Checking circular link        res = Math.Min(res, Math.Abs(arr[n - 1] - arr[0]));         Console.Write("Min Difference = " + res);    }     // driver code    public static void Main()    {        int[] a = { 10, 12, 13, 15, 10 };        int n = a.Length;        minAdjDifference(a, n);    }} // This code is contributed by Anant Agarwal// and improved by Anuj Sharma.
<?php// PHP program to find maximum// difference between adjacent// elements in a circular array. function minAdjDifference($arr, $n){    if ($n < 2)        return;         // Checking normal    // adjacent elements    $res = abs($arr[1] - $arr[0]);    for ($i = 2; $i < $n; $i++)        $res = min($res,               abs($arr[$i] -               $arr[$i - 1]));         // Checking circular link    $res = min($res, abs($arr[$n - 1] -                     $arr[0]));         echo "Min Difference = ", $res;} // Driver Code$a = array(10, 12, 13, 15, 10);$n = count($a);minAdjDifference($a, $n); //This code is contributed by anuj_67//and improved by Anuj Sharma.?>
<script> // Javascript program to find maximum difference// between adjacent elements in a circular array. function minAdjDifference( arr, n){    if (n < 2)        return;     // Checking normal adjacent elements    let res = Math.abs(arr[1] - arr[0]);    for (let i = 2; i < n; i++)        res = Math.min(res, Math.abs(arr[i] - arr[i - 1]));     // Checking circular link    res = Math.min(res, Math.abs(arr[n - 1] - arr[0]));     document.write("Min Difference = " + res);} // driver code     let a = [ 10, 12, 13, 15, 10 ];    let n = a.length;    minAdjDifference(a, n); </script>
Output: 
Min Difference =  0
Time Complexity: O(N), as we are using a loop to traverse N times.
Auxiliary Space: O(1), as we are not using any extra space. 
https://youtu.be/G
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