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C# Intermediate C# Abstraction Abstract Members

i have no clue

I made SequenceDetector.Scan method as an abstract as I was told, but it throws an error. I have no clue to fix it.

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

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

        public abstract bool Scan(int[] sequence)
        {
            LastScannedSequence = sequence;
            return true;
        }
    }
}

1 Answer

Steven Parker
Steven Parker
231,198 Points

You correctly changed the designation, but an abstract class definition also has no body.

Yes, that is what I got from an error. Acutually I don't quite get what it says. Does it mean that

 public abstract bool Scan(int[] sequence)
        {
            LastScannedSequence = sequence;
            return true;
        }
should be like this?
 public abstract bool Scan(int[] sequence)
        {

        }
Steven Parker
Steven Parker
231,198 Points

That would stil be a body, just an empty one. For no body at all:

 public abstract bool Scan(int[] sequence);