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C# Intermediate C# Polymorphism Virtual Methods

Posted by Erik Hainer
Erik Hainer
3,049 Points

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
231,268 Points
Steven Parker
Steven Parker
231,268 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.