Swift Set Collection and Common Methods Detailed Summary

// Create Setvar set: Set<Int> = [1, 2, 3]
var set2 = Set(arrayLiteral: 1, 2, 3)

// set gets the minimum value()

// Get the first element, in a different orderset[]


// Get elements through subscripts, you can only move backwards, not forwards// Get the second elementset[(after: )]

// Get several elements after a certain subscriptset[(, offsetBy: 2)]

// Get the number of elements

//Judge empty setif  {
   print("set is empty")
}

// Determine whether the set contains an elementif ((3)) {
    print("set contains 3")
}

// Insert(0)

// Remove(2)
()

// Remove elements in the specified position and need to use ! Unpacking, you get the Optional type. If you remove non-existent elements, EXC_BAD_INSTRUCTION(at: (of: 1)!)

()


var setStr1: Set<String> = ["1", "2", "3", "4"]
var setStr2: Set<String> = ["1", "2", "5", "6"]

// Set to get the intersection(setStr2) // {"2", "1"}

// Set to get the complement of the intersection(setStr2) // {"4", "5", "3", "6"}

// Set to collect and combine(setStr2) // {"2", "3", "1", "4", "6", "5"}

// Set takes the relative complement (difference set), (B), that is, take the element set that belongs to A but not B(setStr2) // {"3", "4"}

var eqSet1: Set<Int> = [1, 2, 3]
var eqSet2: Set<Int> = [3, 1, 2]

//Judge Set set equalityif eqSet1 == eqSet2 {
    print("When all elements in a collection are equal, the two sets are equal, and have nothing to do with the order of the elements")
}

let set3: Set = [0, 1]
let set4: Set = [0, 1, 2]

//Judge subset(of: set4) // set3 is a subset of set4, true(of: set4) // set3 is a true subset of set4, true
// Judgment superset(of: set3) // set4 is a superset of set3, true(of: set3) // set4 is the true superset of set3, true

// traverse elementsfor ele in set4 {
    print(ele)
}

// traverse the enumeration of the collectionfor ele in () {
    print(ele)
}

// Subscript traversalfor index in  {
    print(set4[index])
}

//Sort from small to large and then go throughfor ele in (by: <) {
    print(ele)
}