Collections and Control Flow Code Challenge error

Question

For the code challenge I get the error: n is a "let" constant. Why is this?
var results: [Int] = []
for n in 1...100 {
    // Enter your code below
    if n % 7 == 0 && n % 2 != 0 {
    results.append(n)
    n++
    }else{
    n++
    }
    // End code 
}
```logicalOperators.swift
var results: [Int] = []
for n in 1...100 {
    // Enter your code below
    if n % 7 == 0 && n % 2 != 0 {
    results.append(n)
    n++
    }else{
    n++
    }
    // End code 
}
```

jcorum · Answer

Close.  But there's no need for you to increment n in the loop.  That's what the loop does automatically.
```swift
for n in 1...100 {
    // Enter your code below
    // Enter your code below
    if n % 7 == 0 && n % 2 != 0 {
      results.append(n)
    }
    // End code 
}
```
When you say for n in 1...100 you are saying for each n in that range.  So the first time through the loop n will be 1, the next time through it will be 2, etc.
What you were trying to do is change the value of n inside the loop, and swift was telling you you can't do that, as it considers n to be a constant.

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Ben Kachelhoffer

Ben Kachelhoffer

Collections and Control Flow Code Challenge error

Ben Kachelhoffer

Ben Kachelhoffer

1 Answer

jcorum

jcorum