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C# Intermediate C# Polymorphism Virtual Methods

RepeatDetector.Scan doesn't detect repetitions.

What am I missing here? Nothing looks wrong here to me. Unless TTH wants a specific implementation?

SequenceDetector.cs
namespace Treehouse.CodeChallenges
{
    class SequenceDetector
    {
        public virtual bool Scan(int[] sequence)
        {
            return true;
        }
    }
}
RepeatDetector.cs
namespace Treehouse.CodeChallenges
{
    class RepeatDetector : SequenceDetector
    {
        public override bool Scan(int[] sequence)
        {
            for(int i = 1; i < sequence.Length; i++)
            {
                if(sequence[i] == sequence[i]-1)
                {
                    return true;
                }
            }
            return false;
        }
    }
}

1 Answer

Steven Parker
Steven Parker
229,645 Points

You're really close! But instead of decrementing the value of the indexed item, decrement the index instead so you can compare with the previous item:

//              if(sequence[i] == sequence[i]-1)   // original
                if (sequence[i] == sequence[i-1])  // fixed

-_- Thanks... In the back of my mind I knew it was going to be something I did.