Sock Merchant

using System.CodeDom.Compiler;
using System.Collections.Generic;
using System.Collections;
using System.ComponentModel;
using System.Diagnostics.CodeAnalysis;
using System.Globalization;
using System.IO;
using System.Linq;
using System.Reflection;
using System.Runtime.Serialization;
using System.Text.RegularExpressions;
using System.Text;
using System;

class Solution {

    // Complete the sockMerchant function below.
    static int sockMerchant(int n, int[] ar)
    {
        var socksByColor = new Dictionary<int, int>();
        foreach (var color in ar)
        {
            if (socksByColor.TryGetValue(color, out var socks))
            {
                socks++;
            }
            else
            {
                socks = 1;
            }
            socksByColor[color] = socks;
        }

        int pairsTotal = 0;
        foreach (var socksForColor in socksByColor)
        {
            var pairs = socksForColor.Value / 2;
            pairsTotal += pairs;
        }

        return pairsTotal;
    }

    static void Main(string[] args) {
        TextWriter textWriter = new StreamWriter(@System.Environment.GetEnvironmentVariable("OUTPUT_PATH"), true);

        int n = Convert.ToInt32(Console.ReadLine());

        int[] ar = Array.ConvertAll(Console.ReadLine().Split(' '), arTemp => Convert.ToInt32(arTemp))
        ;
        int result = sockMerchant(n, ar);

        textWriter.WriteLine(result);

        textWriter.Flush();
        textWriter.Close();
    }
}