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C# C# Collections Lists Lists

Herman Vicens
Herman Vicens
12,540 Points
Posted by Herman Vicens
Herman Vicens
12,540 Points

Don't know where to get the value being passed

The directions are not clear as to where or how the program will get the required value. The code is ready but no value is being passed.

MathHelpers.cs 
using System;
using System.Collections.Generic;
namespace Treehouse.CodeChallenges
{
    public static class MathHelpers
    {
        public static List<int> GetPowersOf2(int factor)
        {

             Console.Write("Factor  --> "+factor);

             List<int> powers = new List<int>(10);

             for (int x=0 ; x < factor ; x++)
             {
                 powers[x] = (int)Math.Pow(2,x) ;
                 Console.Write(" Power of 2 a la "+x+" =  "+powers[x]);
             }
            return powers;
        }

    }
}

1 Answer

Chris Adamson
Chris Adamson
132,143 Points
Chris Adamson
Chris Adamson
132,143 Points

You're pretty close, you need to imports, one for the generic List, and the other for Math.Pow, each number should be added via powers.Add, and the loop should go <= to get the correct count of numbers.

using System.Collections.Generic;
using System;

namespace Treehouse.CodeChallenges
{
    public static class MathHelpers
    {
        public static List<int> GetPowersOf2(int factor)
        {
             var powers = new List<int>();

             for (int x=0 ; x <= factor ; x++)
             {
                 powers.Add((int)Math.Pow(2,x));
             }
            return powers;
        }                
    }
}