Arrays - Parallel Arrays

Introduction

The Mode of an array is the count of the element that appears most in the array.

Code

The code below uses a manually created array of integer values but the code cam easily be adapted to work with any type or size of array.

namespace ModeOfAnArray
{
    internal class Program
    {
        static void Main(string[] args)
        {
            const int PhysicalSize = 25;
            int[] numbers = { 2, 3, 6, 8, 9, 13, 22, 29, 33, 41, 42, 45, 45, 46, 47, 48, 57, 59, 59, 65, 83, 83, 91, 99, 100 };
            int mode;
            DisplayArray(numbers, PhysicalSize);

            mode = FindMode(numbers, PhysicalSize);
            Console.WriteLine($"\nThe mode of the array is {mode}.");

            Console.ReadLine();
        }//eom

        static int FindMode(int[] numbers, int size)
        {
            //find the highest number in the array, which was previously sorted
            int max = numbers[size - 1];
            int top = max + 1;
            int[] count = new int[top];
            //initialize the count array to all 0's
            for (int index = 0; index < top; index++)
            {
                count[index] = 0;
            }
            //store the count of each element of the input array
            for (int index = 0; index < size; index++)
            {
                count[numbers[index]]++;
            }
            //mode is the index with the maximum count
            int mode = 0;
            int modeCount = count[0];
            for (int index = 1; index < top; index++)
            {
                if (count[index] > modeCount)
                {
                    modeCount = count[index];
                    mode = index;
                }
            }
            return mode;
        }//end of FindMode

        static void DisplayArray(int[] numbers, int size)
        {
            Console.WriteLine("The array data is:");
            for (int index = 0; index < size; index++)
            {
                Console.Write($"{numbers[index]}  ");
            }
        }//end of DisplayArray
    }//eoc
}//eon

Question: In this example, why is the mode 45 and not 59?

If the data in the array was:

int[] numbers = { 2, 3, 6, 9, 9, 13, 22, 29, 33, 41, 42, 45, 45, 46, 47, 48, 57, 59, 59, 65, 83, 83, 91, 99, 100 };

the mode would be 9. The mode method finds the first number that has the highest count number in the array. If the next highest count is the same count value, the first one is returned.

Changing the array data to:

int[] numbers = { 2, 3, 6, 9, 9, 13, 22, 29, 33, 41, 42, 45, 45, 46, 47, 48, 57, 59, 59, 59, 83, 83, 91, 99, 100 };

returns a mode of 59.

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