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Start your free trialJustin Cure
5,001 PointsCode compiles correctly, but list returned does not contain the correct number of items?
Trying to complete the GetPowersOf2 coding challenge in the C# Collections module on Lists, and I can't get my code to return a list with the correct number of items. The code compiles, and I believe I'm calculating the expected results correctly, but I'm not sure why it's not populating the correct number of items. My for loop iterates from 0 to the value passed in to the GetPowersOf2 method, so I don't see what the problem is.
using System.Collections.Generic;
using System;
namespace Treehouse.CodeChallenges
{
public static class MathHelpers
{
public static List<int> GetPowersOf2(int value)
{
List<int> powersOf = new List<int>();
double val = 2;
for(var i = 0; i < value; i++)
{
double result = Math.Pow(val, i);
int power = Convert.ToInt32(result);
powersOf.Add(power);
}
return powersOf;
}
}
}
1 Answer
andren
28,558 PointsMy for loop iterates from 0 to the value passed in to the GetPowersOf2 method, so I don't see what the problem is.
Since the condition for your loop is i
less than value
the loop will not run when i
is actually equal to the value passed in. So if 4 is passed in it will only calculate the power up to 3.
If you change your condition to less than or equal to like this:
using System.Collections.Generic;
using System;
namespace Treehouse.CodeChallenges
{
public static class MathHelpers
{
public static List<int> GetPowersOf2(int value)
{
List<int> powersOf = new List<int>();
double val = 2;
for(var i = 0; i <= value; i++) // Changed < to <=
{
double result = Math.Pow(val, i);
int power = Convert.ToInt32(result);
powersOf.Add(power);
}
return powersOf;
}
}
}
Then your code will work.
Justin Cure
5,001 PointsJustin Cure
5,001 PointsThis worked! Thank you for your help.