swift実践入門output Chapter４ コレクションを表す型 前編

コレクションとは値の集まりのこと

配列を表す
Array< Element>型

辞書を表す
Dictionary< Key, Value>型

範囲を表す
Range< Bound>型

配列を表す Array< Element >型

実際にはArray< Int >型、Array< String >型のように使う

chapter4.swift

let a = [1,2,3]
let b = ["a","b","c"]

let array :[Int] = []

var strings = ["aaa","bbb","ccc"]
var strings1 = strings[0]
print(strings1)

//aaa

strings[2] = "gagaga"
print(strings)

["aaa", "bbb", "gagaga"]

//末尾に追加
strings.append("yamato")
print(strings)

//["aaa", "bbb", "gagaga", "yamato"]

//任意の位置に追加
strings.insert("mama", at: 2)
print(strings)

//["aaa", "bbb", "mama", "gagaga", "yamato"]


//削除は３タイプ
var integer = [1,2,3,4,5]
integer.remove(at: 2)
integer

integer.removeLast()
integer

integer.removeAll()
integer

辞書を表す　Dictionary<　Key, Value　>型

chapter4.swift

let dictionary = ["Key":1]
let value = dictionary["key"]
print(value)

//["key": 1]

//変更
var dictionary1 = ["key": 2]
dictionary1["key"] = 1
print(dictionary1)
//追加
var dictionary2 = ["key":3]
dictionary2["key2"] = 4
print(dictionary2)

//["key2": 4, "key": 3]

//削除
var dictionary3 = ["key":5]
dictionary3["key"] = nil
print(dictionary3)

//[:]

範囲型　範囲を表す型

chapter4.swift

//末尾を含まない範囲　countableRange<Bound>型
let range = 1..<4
for value in range {
    print(value)
}

//1
//2
//3

//... 末尾を含む型 CountableClosedRange<Bound>型

let range2 = 1...4
for value in range2 {
    print(value)
}

//1
//2
//3
//4


let range3 = 1...5
print(range3.upperBound)
print(range3.lowerBound)

//5
//1


//値が範囲に含まれるかの判定

let range4 = 1..<10

print(range4.contains(4))
print(range4.contains(10))

//true
//false