Daily Coding Problem: Problem #2, C#

Daily Coding Problem: Problem #2

/*Good morning! Here's your coding interview problem for today.
This problem was asked by Uber.
Given an array of integers, return a new array such that each element at index i of the new array is the product of all the numbers in the original array except the one at i.
For example, if our input was [1, 2, 3, 4, 5], the expected output would be [120, 60, 40, 30, 24]. If our input was [3, 2, 1], the expected output would be [2, 3, 6].
Follow-up: what if you can't use division?*/

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.RegularExpressions;

namespace Rextester
{
    public class Program
    {
        public static void Main(string[] args)
        {
            Console.WriteLine(AreEqual(MakeArray(new List<int>(){ 1, 2, 3, 4, 5 }), 
                                       new List<long>(){ 120, 60, 40, 30, 24 }));
            Console.WriteLine(AreEqual(MakeArray(new List<int>(){ 3, 2, 1 }), 
                                       new List<long>(){ 2, 3, 6 }));
            Console.WriteLine(AreEqual(MakeArray(new List<int>(){ 1, 2 }), 
                                       new List<long>(){ 2, 1 }));
            Console.WriteLine(AreEqual(MakeArray(new List<int>(){ 1 }), 
                                       new List<long>(){ }));
        }
        
        static List<long> MakeArray(List<int> list)
        {
            if(list.Count == 1)
            {
                return new List<long>();
            }
            var upTo = Enumerable.Range(0, list.Count).Select(f => (long)f).ToList<long>();
            var downTo = Enumerable.Range(0, list.Count).Select(f => (long)f).ToList<long>();

for(int i=0; i<list.Count; i++)
            {
                upTo[i] = i > 0 ? list[i] * upTo[i-1] : list[i];
            }

for(int i=list.Count - 1; i >= 0; i--)
            {
                downTo[i] = i < list.Count - 1 ? list[i] * downTo[i+1] : list[i];
            }


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