Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

C# Intermediate C# Polymorphism Virtual Methods

Posted by Herman Vicens
Herman Vicens
12,540 Points

Detecting duplicate entries in the array when there are none,..

It appears that this code is finding duplicates in the array when there are none. I can't see why the code is not working. Any ideas?

SequenceDetector.cs 
namespace Treehouse.CodeChallenges
{
    class SequenceDetector
    {
        public virtual bool Scan(int[] sequence)
        {
            return true;
        }
    }


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

2 Answers

Steven Parker
Steven Parker
241,434 Points
Steven Parker
Steven Parker
241,434 Points

The initialization of isDuplicated is outside of the method.

This means once it is set to true, it will never be false again in subsequent calls.

It doesn't really need to be a class variable anyway. You might just move the variable itself into the method.

Herman Vicens
Herman Vicens
12,540 Points
Herman Vicens
Herman Vicens
12,540 Points

Thanks. So obvious and yet couln't see it. Thanks for your help.