Initialization of array and dictionary creation in Swift

First look at Swift's method of initializing array, and the following types take int as an example

var a1 = [1, 2, 3]

var a2:int[] = [1, 2, 3]

var a3:int[] = int[] ([1, 2, 3])

var a4:int[] = array<int> ([1,2,3])

var a5:array<int> = [1,2,3,]

var a6 = array<int> ([1,2,3])

var a7:array<int> = array<int> ([1,2,3])

The next step is dictionary, because its internal Init method is implemented with a much less initialization method, with string, string as an example

var D1 = ["1": "2"]

var d2:dictionary<string, string> = ["1": "2"]

var d3:dictionary<string, string> = dictionary<string, string> ()

var d4 = dictionary<string, string> ()

The methods listed above are also studied and tested by the Swift programming language, if there is any other way, please leave a message for your friends.