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

Posted by Sam Murphy
Sam Murphy
10,469 Points

how do i do a check to see if a number is a multiple of 7 and odd in a for in loop?

here is the code challenge: For this challenge, we'd like to know in a range of values from 1 to 100, how many numbers are both odd, and a multiple of 7.

To start us off, I've written a for loop to iterate over the desired range of values and named the local constant n. Your job is to write an if statement inside the for loop to carry out the desired checks.

If the number is indeed both an odd number and a multiple of 7, append the value to the results array provided.

Hint: To check for an odd number use the not operator to check for "not even"

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

for n in 1...100 {
    // Enter your code below
    if results != 1 && results *= 7 {
    }
    // End code 
}

1 Answer

Duarte Monteiro
Duarte Monteiro
22,300 Points
Duarte Monteiro
Duarte Monteiro
22,300 Points

It's with n that you have to check the condition not results. To check if the number are multiple of use the Remainder Operator %. This lets you know if a number is cleanly divisible if the results is 0.

is multiple of 7

6 % 7 == 0 // false
7 % 7 == 0 // true
8 % 7 == 0 // false

is odd (is not multiple of 2)

1 % 2 != 0 // true
2 % 2 != 0 // false
3 % 2 != 0 // true
4 % 2 != 0 // false

var results: [Int] = []

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

    // if the remainer of n times 7 is equal to 0 (clean)
    // and
    // if the remainder of n times 2 is not equal to 0 (not clean)
    if n % 7 == 0 && n % 2 != 0 {
        // append it to the results array
        results.append(n)
    }
}

// results [7, 21, 35, 49, 63, 77, 91]

Keep on coding ? @du5rte