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C# Intermediate C# Abstraction Abstract Members

Calvin Secrest
Calvin Secrest
24,815 Points

Need help

Confused about how to Change SequenceDetector.Scan to an abstract method.

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

1 Answer

Brian DuPont
Brian DuPont
30,448 Points

In the SequenceDetector class, you need to change virtual to abstract, and also get rid of the method body. So it would be just like this: public abstract bool Scan(int[] sequence); We want the class inheriting this method to override and implement the method with a method body.