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# subscript(_:)

Accesses the element at the specified position.

```
override subscript(position: Self.Index) -> Self.Element { get set }
```

## Parameters

`position`

The position of the element to access. `position`
must be a valid index of the collection that is not equal to the
`endIndex` property.

## Overview

For example, you can replace an element of an array by using its
subscript.

```
var streets = ["Adams", "Bryant", "Channing", "Douglas", "Evarts"]
streets[1] = "Butler"
print(streets[1])
// Prints "Butler"
```

You can subscript a collection with any valid index other than the
collection’s end index. The end index refers to the position one
past the last element of a collection, so it doesn’t correspond with an
element.

> Complexity: O(1)

---

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