Lab task 03 for C#

lab_task_03.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            Pledge[] pledgeArray = new Pledge[2];
            float amount = 0.00f;

            pledgeArray[0] = new Pledge(200);
            pledgeArray[1] = new SpecialPledge(50);

            pledgeArray[0].display();
            pledgeArray[1].display();

            Console.WriteLine("Enter the pledged amount for Pledge Object ");
            amount = float.Parse(Console.ReadLine());
            pledgeArray[0].add_pledge(amount);

            Console.WriteLine("Enter the pledged amount for Special Pledge Object ");
            amount = float.Parse(Console.ReadLine());
            pledgeArray[1].add_pledge(amount);


            pledgeArray[0].display();
            pledgeArray[1].display();
        }
    }


    // pledge class
    class Pledge { 
        
        private float amt1;

        public Pledge() { }
        public Pledge(float amt1 = 1.00f) {
            this.amt1 = amt1;
        }

        public virtual void add_pledge(float amt1) {
            this.amt1 = amt1;
        }

        public virtual float get_pledge() {
            return this.amt1;
        }


        public virtual void display(){
            Console.WriteLine("Pledge Object");
            Console.WriteLine("Pledged Amount $: " + this.amt1);
        }

    }



        class SpecialPledge : Pledge {

            private float[] amt2;

            public SpecialPledge() { }
            public SpecialPledge(float value)
                : base(value)
            {
               this.amt2 = new float[12];
               for (int i = 0; i < this.amt2.Length;i++)
               {
                   this.amt2[i] = value;
               }
            }   
     

            //overrids method
            public override void add_pledge(float value)
            {
                Console.WriteLine("Enter Month: ");
                int month = int.Parse(Console.ReadLine()) - 1;
                this.amt2[month] = value;
            }


            public override float get_pledge()
            {
                float grandTotal = 0.00f;
                for (int i = 0; i < this.amt2.Length;i++ )
                {
                    grandTotal += this.amt2[i];
                }
                return grandTotal;
            }


            public override void display() {


                Console.WriteLine("Special Pledge Object ");
                for (int i = 0; i < this.amt2.Length;i++ )
                {
                    Console.WriteLine("Pledged Amount for month {0} $: {1}",i+1,this.amt2[i]);
                }
            }

        }
    
    }