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C# C# Collections Lists Lists

Calvin Secrest
Calvin Secrest
24,815 Points
Posted by Calvin Secrest
Calvin Secrest
24,815 Points

Getting Past the C# List<T> for list of integers Challange

The code below works fine in the IDE, but will not let me pass the challenge.

Directions: "Create a static method named GetPowersOf2 that returns a list of powers of 2 from 0 to the value passed in. So if 4 was passed in, the function would return { 1, 2, 4, 8, 16 }. The System.Math.Pow method will come in handy."

Error: " Bummer! Does MathHelpers.GetPowersOf2 return List`1?"

Does anyone now what the Code Challenge is looking for (besides what its asking)

Thanks

MathHelpers.cs 
using System.Collections.Generic;
using System;

namespace Treehouse.CodeChallenges
{
    public static class MathHelpers
    {
        public static List<int> GetPowersOf2(int input)
        {
            var returnList = new List<double>();
            for (int 1 = 0; i <= input; i++)
            {
                returnList.Add((int)Math.Pow(2, i));
            }   
        }
    }
}

2 Answers

Eduardo Parra San Jose
Eduardo Parra San Jose
12,579 Points
Eduardo Parra San Jose
Eduardo Parra San Jose
12,579 Points

Hi,

I hope the following tips helps out to solve the challenge:

  • The GetPowersOf2 method performs actions but it doesn't include a return statement to return the List
  • Variable names cannot start with a number, so in the for loop the variable cannot be called 1, I guess what you wanted was to call it i
  • In the signature of the method it says a list of int will be returned, but the returnList type is a list of double

Many thanks. Have a nice day, edu

Calvin Secrest
Calvin Secrest
24,815 Points
Calvin Secrest
Calvin Secrest
24,815 Points

Thank you for this assistance!

Eduardo Parra San Jose
Eduardo Parra San Jose
12,579 Points
Eduardo Parra San Jose
Eduardo Parra San Jose
12,579 Points

You're welcome :)