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iOS Swift 2.0 Collections and Control Flow Control Flow With Loops For In Loops

Posted by John Ajayi
John Ajayi
6,669 Points

For in Loops Challenge

Hi Can anyone help on the For In Loops Challenge???

I completed it but when i did it in Xcode it comes up with an Error.

The Challenge task is below.

For this challenge, we're going to use a for in loop to compute the multiplication table for 6 and append the results to an array.

To start off, I've created an empty array of type Int and assigned it to a variable named results. Note that we have to explicitly declare the type here so that the compiler knows this array will hold Int values.

Your task for this step is to create a for in loop that iterates over a range. Multiplication tables typically range from 1 to 10 (with 10 included) so the range you are iterating over should go from 1 to 10.

For in loops also define a constant that temporarily stores the value in the iteration process. For the loop you're writing, name this constant multiplier.

Martin Wildfeuer
Martin Wildfeuer
Courses Plus Student 11,071 Points
Martin Wildfeuer
Martin Wildfeuer
Courses Plus Student 11,071 Points

Please update this post with your code, so we can go through it. Moreover, please let us know what the Xcode error is. Thanks!

2 Answers

M T
M T
7,668 Points
M T
M T
7,668 Points

Could you post the code you used to complete the challenge?

John Ajayi
John Ajayi
6,669 Points

Ok Apologies

Step 1 asked the following:

For this challenge, we're going to use a for in loop to compute the multiplication table for 6 and append the results to an array.

To start off, I've created an empty array of type Int and assigned it to a variable named results. Note that we have to explicitly declare the type here so that the compiler knows this array will hold Int values.

Your task for this step is to create a for in loop that iterates over a range. Multiplication tables typically range from 1 to 10 (with 10 included) so the range you are iterating over should go from 1 to 10.

For in loops also define a constant that temporarily stores the value in the iteration process. For the loop you're writing, name this constant multiplier.

The code i put was:

var results: [Int] = [6]

for multiplier in 1...10 {print("(multiplier) times (results) is equal to (multiplier) * (results)")}

The Error:

in the Debug area the output shows:

1 times [6] is equal to 1 * [6] 2 times [6] is equal to 2 * [6] 3 times [6] is equal to 3 * [6] 4 times [6] is equal to 4 * [6] 5 times [6] is equal to 5 * [6] 6 times [6] is equal to 6 * [6] 7 times [6] is equal to 7 * [6] 8 times [6] is equal to 8 * [6] 9 times [6] is equal to 9 * [6] 10 times [6] is equal to 10 * [6]

which is incorrect. I think it has something to do with the [Int] but this was already given in the challenge so i do not believe i should be changing it. but when i changed it in Xcode (removing [Int] and leaving 6 with no []) it worked.

The second problem was with challenge number 2:

Inside the body of the loop, we're going to use the multiplier to get the multiple of 6. For example, if the multiplier is 1, then the multiple is 1 times 6, which is equal to 6. 
Once you have a value, append it to the results array. This way once the for loop has iterated over the entire range, the array will contain the first 10 multiples of 6.

The code i used was:

var results: [Int] = [6, 12, 18, 24, 30, 36, 42, 48, 54, 60]

for multiplier in 1...10 {print("(multiplier) times (results) is equal to (multiplier) * (results)")}

It worked and i completed the challenge but in Xcode it show up the same as it did in the Debug area above but with the additional numbers

hope this make sense

Thanks for your help

ahyuursagv
ahyuursagv
18,371 Points
ahyuursagv
ahyuursagv
18,371 Points

On part 2 of 2 this worked for me. It might have just been me but the wording in the challenge seemed slightly confusing so I had trouble understanding what was expected too at first. Hope this helps.

var results: [Int] = []

for multiplier in 1...10 {
  results.append(multiplier * 6)
}