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 the absolute difference between two elements,  and  (where ), to be the absolute 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);
    }
}