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C# C# Objects Loops and Final Touches For Loops

Posted by Sarker Jawad Islam
Sarker Jawad Islam
3,587 Points

Cannot use operand "+=" for the frog code challenge for some reason

FrogStats.cs(11,17): error CS0019: Operator +=' cannot be applied to operands of typedouble' and `Treehouse.CodeChallenges.Frog' That is the error I am getting.

I tried using + just to test and it seems like any operand I use causes an error.

Not sure what I am doing wrong

FrogStats.cs 
namespace Treehouse.CodeChallenges
{
    class FrogStats
    {
        public static double GetAverageTongueLength(Frog[] frogs)
        {   double result;
            int num = frogs.Length;

            for(int i=0; i< frogs.Length; i++)
            {
                result += frogs[i];
            }
            result /= num;

            return result;
        }
    }
}
Frog.cs 
namespace Treehouse.CodeChallenges
{
    public class Frog
    {
        public int TongueLength { get; }

        public Frog(int tongueLength)
        {
            TongueLength = tongueLength;
        }
    }
}

1 Answer

Steven Parker
Steven Parker
231,236 Points
Steven Parker
Steven Parker
231,236 Points

The "preview" button error message is telling you that you're trying to add the frog itself, so instead use just the TongueLength:

                result += frogs[i].TongueLength;

The other issue is that you cannot use the '+=' operator on variables that haven't been initialized (only declared), so give "result" an initial value:

            double result = 0;
Sarker Jawad Islam
Sarker Jawad Islam
3,587 Points

Thank you very much that solved it!.