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Start your free trial###### Eddie Aguilar

2,393 Points# I am literally stuck and cannot even think of what I am supposed to write. HELP??

I have watched the all of the content leading up to this point and have a basic understanding of it so far. But for this challenge I cannot, whatsoever think of what I am supposed to write. I have watched the 2 videos prior to this challenge about 4 times and have a decent understanding of it. Again for this challenge, I cannot move forward and was wondering I could have someone give me somewhat of a walkthrough.

```
var results: [Int] = []
for n in 1...100 {
// Enter your code below
NO IDEA WHAT TO WRITE
// End code
}
```

## 1 Answer

###### andren

28,552 PointsSure I can provide a step by step walkthrough.

The first thing you have to do in this task is figure out if the number in `n`

is odd. In an earlier lecture you were shown that you can use the % remainder (modulus) operator to figure out if something is even.

if you divide a number by 2 and it has a remainder of 0 then it is even. If you use the != (not equal) operator like this `n % 2 != 0`

you will check if a number is not even. If a number is not even then it must be odd.

The second thing you need to do is check that `n`

is a multiple of 7. This can also be accomplished using the remainder operator. If the remainder of `n`

and 7 is 0 then `n`

has to be a multiple of seven.

So the first line of loop should look like this:

```
var results: [Int] = []
for n in 1...100 {
if n % 2 != 0 && n % 7 == 0 { // Checks if n is both an odd number and a multiple of seven
}
}
```

All that is left to do after that is to append `n`

to the `results`

array. That can be done pretty simply by using the `append`

method. I'll illustrate below:

```
var results: [Int] = []
for n in 1...100 {
if n % 2 != 0 && n % 7 == 0 { // Checks if n is both an odd number and a multiple of seven
results.append(n) // Append n to the results array
}
}
```

And that is actually all you have to do, the above code will add odd numbers that are multiples of seven to the `results`

array.