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C# Intermediate C# Abstraction Abstract Classes

Change SequenceDetector to an abstract class.

task 1 of 1

SequenceDetector.cs
namespace Treehouse.CodeChallenges
{
    public class SequenceDetector
    {
        public virtual string Description => "";

        public int[] LastScannedSequence { get; protected set; }

        public virtual bool Scan(int[] sequence)
        {
            LastScannedSequence = sequence;
            return true;
        }
    }
}
RepeatDetector.cs
namespace Treehouse.CodeChallenges
{
    public class RepeatDetector : SequenceDetector
    {
        public override string Description => "Detects repetitions";

        public override bool Scan(int[] sequence)
        {
            LastScannedSequence = sequence;

            if(sequence.Length < 2)
            {
                return false;
            }

            for(int i = 1; i < sequence.Length; ++i)
            {
                if(sequence[i] == sequence[i-1])
                {
                    return true;
                }
            }

            return false;
        }
    }
}
Shadab Khan
Shadab Khan
5,470 Points

Hi Noel, You haven't explained the problem here. Can you please elaborate ? Cheers.

1 Answer

Demari Moore
Demari Moore
3,075 Points

Hi, to change the Sequence Detector class to an abstract class add the word abstract in front the class.

public abstract class SequenceDetector

{

}

An abstract class inherits non-abstract methods so no need for override of the repeatDetector method and property. You will need to remove override from your method and property in the RepeatDetector class or set these to abstract within the abstract class.