This algorithm focuses on merging two arrays and sorting them in increasing order.

MergeArraysInIncreasingOrder.cs

class Program
    {
        private static List<int> SingleArray { get; set; } = new List<int>();

        static void Main(string[] args)
        {
            int[] classA = { 13, 15, 19 };
            int[] classB = { 11, 13, 18 };

            AddFirstArrayIntoSingleArray(classA);
            AddSecondArrayIntoSingleArray(classB);
            MergeArraysInIncreasingOrder(SingleArray);
            PrintArray(SingleArray);
        }

        public static void AddFirstArrayIntoSingleArray(int[] classA)
        {

            if (classA == null) { }
            else
            {
                SingleArray.AddRange(classA);
            }
        }

        public static void AddSecondArrayIntoSingleArray(int[] classB)
        {

            if (classB == null) { }
            else
            {
                SingleArray.AddRange(classB);
            }
        }

        public static void MergeArraysInIncreasingOrder(List<int> singleArray)
        {
            if (singleArray == null) { }
            else
            {
                int max = singleArray.Max();
                int min = singleArray.Min();
                int range = max - min + 1;
                int[] count = new int[range];
                int[] output = new int[singleArray.Count];
                for (int i = 0; i < singleArray.Count; i++)
                {
                    count[singleArray[i] - min]++;
                }
                for (int i = 1; i < count.Length; i++)
                {
                    count[i] += count[i - 1];
                }
                for (int i = singleArray.Count - 1; i >= 0; i--)
                {
                    output[count[singleArray[i] - min] - 1] = singleArray[i];
                    count[singleArray[i] - min]--;
                }
                for (int i = 0; i < singleArray.Count; i++)
                {
                    singleArray[i] = output[i];
                }
            }
            
        }

        public static void PrintArray(List<int> singleArray)
        {
            if (singleArray == null) { }
            else
            {
                for (int i = 0; i < singleArray.Count; i++)
                {
                    Console.Write(singleArray[i] + " ");
                }
                Console.WriteLine("");
            }
            
        }


    }

Hello @Ezeji, thank you for participating in Week 5 of #AlgorithmFridays.

This is a decent attempt at solving the problem and I like your smart approach of concatenating both arrays and then sorting them. I thought to highlight a couple of things:

• In terms of code cleanness, you have two functions AddFirstArrayIntoSingleArray and AddSecondArrayIntoSingleArray that are pretty much doing the same thing. In line with the DRY principle, that could have been one function as shown below:

        public static void AddArrayIntoSingleArray(int[] className)
        {

            if (className== null) { }
            else
            {
                SingleArray.AddRange(className);
            }
        }

So that you can use that one function on lines 10 and 11.

• Another thing I'll like to know is what you think about the memory efficiency of your solution because I see you have created two extra arrays (lists) on lines 56 and 57.

That said in terms of correctness, this was a good shot. Kudos to you!

Do let me know what you think with regards to the feedback and thanks once again for participating.

Hello @meekg33k

Thanks for the feedback. Really, they're helpful as I didn't consider those being that they were an oversight.

Thanks once again.