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iOS Swift 2.0 Collections and Control Flow Control Flow With Conditional Statements Working with Logical Operators

Posted by Justus Aberson
Justus Aberson
1,035 Points

I dont understand what to do.

Hey guys, can someone please explain to me what to do? Thanks.

logicalOperators.swift 
var results: [Int] = []

for n in 1...100 {
    // Enter your code below
    if 
    // End code 
}

2 Answers

Henrik Brüntrup
Henrik Brüntrup
5,485 Points
Henrik Brüntrup
Henrik Brüntrup
5,485 Points

Hi Justus,

you need to use the && operator in the if statement and append the numbers that are both unequal and divisible by 7:

var results: [Int] = []

for n in 1...100 {
    // Enter your code below
    if (n % 2 == 1) && (n % 7 == 0) {
        results.append(n)
    }
    // End code
}

Btw. it is good practice to mark an answer as 'best answer' in your threads, if a successful solution has been posted. It lets others know that the answer has been given and no longer needs to be looked at. I posted an answer to your earlier thread about while-loops and it never received feedback from you.

Justus Aberson
Justus Aberson
1,035 Points

Thanks, Henrik, but I dont understand your code, can you please explain?

Henrik Brüntrup
Henrik Brüntrup
5,485 Points
Henrik Brüntrup
Henrik Brüntrup
5,485 Points

Sure.

Quoting Apple: The remainder operator (a % b) works out how many multiples of b will fit inside a and returns the value that is left over (known as the remainder).

So the line

if (n % 2 == 1) && (n % 7 == 0) {

means, that the remainder operator will work out how many 2s will fit inside 'n' and if the remainder is 1 and (&&) will then work out how many 7s will fit inside 'n' and if there is no remainder, if this is the case it will then

results.append(n)

append 'n' to the 'results' array.

For example 'n' = 14 will not be added to the array because 2 x 7 = 14 -> no remainder - 'n' = 21 will be added because 2 x 10 = 20 (remainder of 1 to 21) or 2 x 11 = 22 (remainder of 1 to 21) and 7 x 3 = 21 ( no remainder)