Sorting to the rescue, another HackerRank problem

This is the problem: https://www.hackerrank.com/challenges/minimum-absolute-difference-in-an-array:

 Consider an array of integers, . We define theabsolute difference between two elements,and(where), to be theabsolute value of.
Given an array of integers, find and print the minimum absolute difference between any two elements in the array.
Input Format
The first line contains a single integer denoting (the number of integers).
The second line contains space-separated integers describing the respective values of .
Constraints
Output Format
Print the minimum absolute difference between any two elements in the array.
Sample Input 0
3
3 -7 0
Sample Output 0
3

One way that I found to solve the problem was in NLogN-time (I think there is a linear solution to this problem too): (quick)sort the input array, assume the best solution to be a[1]-a[0], and check all others a[i+1]-a[i]. Code is below, cheers, Marcelo.



using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
class Solution
{

 static void Main(String[] args)
{
int n = Convert.ToInt32(Console.ReadLine());
string[] a_temp = Console.ReadLine().Split(' ');
int[] a = Array.ConvertAll(a_temp, Int32.Parse);

 Array.Sort(a);
long solution = a[1] - a[0];
for (int i = 1; i < n - 1; i++)
{
long candidate = a[i + 1] - a[i];
if (candidate < solution) solution = candidate;
}
Console.WriteLine(solution);
}
}

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