# Swift Dictionary 扩容机制



## Dictionary

```swift
let dic = ["d": 4, "a": 1, "b": 2, "c": 3]
print(dic)
// ["c": 3, "d": 4, "a": 1, "b": 2]
```

Dictionary 顺序会乱序



## KeyValuePairs

KeyValuePairs 顺序不会乱序

```swift
let kvs: KeyValuePairs = ["d": 4, "a": 1, "b": 2, "c": 3]
print(kvs)
// ["d": 4, "a": 1, "b": 2, "c": 3]
```



开放寻址法