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C# Intermediate C# Polymorphism Virtual Methods

No errors, but now It says it doesn't detect repetitions.

It just doesn't do what it's supposed to now.

SequenceDetector.cs
namespace Treehouse.CodeChallenges
{
    public class SequenceDetector
    {
        public virtual bool Scan(int[] sequence)
        {
            return true;
        }
    }
}
RepeatDetector.cs
namespace Treehouse.CodeChallenges 
{
public class RepeatDetector : SequenceDetector
    {
        public override bool Scan(int[] sequence)
        {
            for(int i=0;i<sequence.Length;i++)
            {
            if (i > 0)
            {
                if (sequence[i] == (sequence[i]- 1))
                {
                return true;
                }
             }
             }
           return false;
        }
    }
}

1 Answer

Steven Parker
Steven Parker
231,198 Points

It looks like you may have placed a bracket in the wrong place. The comparison sequence[i] == (sequence[i]- 1) doesn't compare two different array elements, it compares each element's value with the result of subtracting one from itself (which can never be true).

You probably intended to write sequence[i] == sequence[i - 1] instead.