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C# Intermediate C# Polymorphism Virtual Methods

Subclass the SequenceDetector class call the new class RepeatDetector

task 2 of 3

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

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

        public abstract bool Scan(int[] sequence);

1 Answer

Steven Parker
Steven Parker
229,645 Points

It looks like you did something for task 1 other than what the instructions asked for. The instructions said "Make the Scan method of the SequenceDetector class virtual.", but the code here shows that it was converted into an abstract instead of virtual, and the class itself was also converted into an abstract.

While this may pass the automated validation for task 1, it means you cannot complete task 2 without also implementing a "Scan" method in the new "RepeatDetector" class.

To have the challenge work as intended, I would suggest starting over with task 1 and perform only the changes in the instructions, and avoid doing anything extra.

You might also want to report the fact that you passed the first task by doing something different to the Support folks. They might want to fix it to prevent students from being confused in the future.