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C# Intermediate C# Polymorphism Virtual Methods

Posted by Stephen Callum
Stephen Callum
2,333 Points

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
231,268 Points
Steven Parker
Steven Parker
231,268 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
Stephen Callum
Stephen Callum
2,333 Points

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