65 lines
1.3 KiB
Markdown
65 lines
1.3 KiB
Markdown
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---
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title: Arrays
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---
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# Arrays
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Arrays are a collection type that stores elements of the **same type** in an **ordered list**.
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### Initialization
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```swift
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//create immutable array.
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let oddNumbers: [Int] = [1,3,5,7,9];
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let evenNumbers = [2,4,6,8];
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//create an empty mutable array
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var numbers = [Int]();
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```
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### Modification
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Add a single element to an array
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```swift
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let someNumber = 0
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numbers.append(someNumber)
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```
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Add multiple elements to an array
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```swift
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numbers += oddNumbers
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numbers.append(contentsOf: evenNumbers)
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```
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Remove and Insert at Index
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```swift
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//remove element from an array at index
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let removedInt = numbers.remove(at: 4)
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//insert element at specific index
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numbers.insert(removedInt, at: 4)
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```
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### Iteration
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You can iterate over a set using a for-in loop. Below are two different ways to do essentially the same thing.
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```swift
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var showNumbers = ""
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numbers = numbers.sorted() //sort the numbers in ascending order
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for i in 0..<numbers.count {
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showNumbers += "\(numbers[i]) "
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}
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print(showNumbers);
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showNumbers = ""
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for i in numbers {
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showNumbers += "\(numbers[i]) "
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}
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print(showNumbers);
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```
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The output(s) for the above are "0 1 2 3 4 5 6 7 8 9"
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#### More Information:
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* [Arrays](https://docs.swift.org/swift-book/LanguageGuide/CollectionTypes.html#ID107)
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