Comparing arrarylist Lists and int array

Comparelist.cs

using System;
using System.Collections;
using System.Collections.Generic;
using System.ComponentModel;
using System.Diagnostics;
using System.Linq;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Threading.Tasks;

namespace myBlank {
    public class Program {
        public static void Main () {
            long duration1 = MeasureA ();
            long duration2 = MeasureB ();
            long duration3 = MeasureC ();
            System.Console.WriteLine ($"Arraylist {duration1}");
            System.Console.WriteLine ($"List<t>{duration2}");
            System.Console.WriteLine ($"Int [] {duration3}");
        }
        private const int nums = 100000000;

        public static long MeasureA () {
            Stopwatch stopwatch = new Stopwatch ();
            stopwatch.Start ();
            ArrayList arrary = new ArrayList ();
            for (int i = 0; i < nums; i++) {
                arrary.Add (i);
            }
            stopwatch.Stop ();
            return stopwatch.ElapsedMilliseconds;

        }

        public static long MeasureB () {
            Stopwatch stopwatch = new Stopwatch ();
            stopwatch.Start ();
            List<int> arr2 = new List<int> ();
            for (int i = 0; i < nums; i++) {
                arr2.Add (i);
            }
            stopwatch.Stop ();
            return stopwatch.ElapsedMilliseconds;

        }

        public static long MeasureC () {
            Stopwatch stopwatch = new Stopwatch ();
            stopwatch.Start ();
            
            int[] array4 = new int[nums];
            for (int i = 0; i < nums; i++) {
                array4[i] = i;
            }

            stopwatch.Stop ();

            return stopwatch.ElapsedMilliseconds;

        }

        public class Calc {
            public static int Add (List<int> numbers) {
                int sum = 0;
                foreach (var nums in numbers) {
                    sum = sum + nums;
                }
                return sum;
            }
        }
    }
}