DynamicArray

using System;
using System.Collections.Generic;
using System.Linq;

class MainClass {
    static void Main() {
       var darr = new DynamicArray();
       Console.WriteLine("length:" + darr.Count());
       darr.Add(1);
       Console.WriteLine("length:" + darr.Count());
       darr.Add(2);
       Console.WriteLine("length:" + darr.Count());
       darr.Add(3);
       Console.WriteLine("length:" + darr.Count());
       darr.Add(44);
       darr.Add(5);
       darr.Add(6);
       darr.Add(7);
       Console.WriteLine("length:" + darr.Count());
       Console.WriteLine("Index 4 of Value:" + darr.Get(4));
       Console.WriteLine("Index 4 of Value:" + darr.Get(8));
       /*Console.WriteLine("Index 4 of Value:" + darr.Get(9));*/
       darr.WriteAllValues();
       Console.WriteLine();
       darr.Add(7);
       darr.Add(7);
       darr.Add(7);
       Console.WriteLine("length:" + darr.Count());
       darr.WriteAllValues();
    }
}

public class DynamicArray
    {
        int capacity = 1;
        int length = 0;
        int[] arr = null;

        public DynamicArray()
        {
            arr = new int[capacity];
        }

        public void Add(int n)
        {
            if (capacity == length)
            {
                this.Resize();
            }
            arr[length] = n;
            length++;
        }

        public void Resize()
        {
            this.capacity *= 2;
            int[] new_arr = new int[capacity];
            for(int i = 0; i < arr.Length; i++)
            {
                new_arr[i] = arr[i];
            }
            arr = new_arr;
        }

        public int Get(int index)
        {
            if(index > arr.Length)
            {
                throw new Exception("Length is outbound");
            }else
            {
                return arr[index - 1];
            }
        }

        public int Count()
        {
            return arr.Length;
        }
        
        public void WriteAllValues()
        {
            foreach(int num in arr)
            {
                Console.Write(num + ",");
            }
        }
    }