3. Dictionary

//: Playground - noun: a place where people can playimport UIKit
 
//mutable dictionary
var legs:Dictionary<String,Int> = [:]
 
var legs2:[String:Int] = [:]
 
legs2["ant"] = 6
legs2["snake"] = 0
print(legs2)
 
var legs3 = ["ant":6, "snake":0, "cheetah":4]
 
print(legs3)
 
legs3["human"] = 2
 
print(legs3)
 
//immutable dictionary
let legs4 = ["ant":6, "snake":0, "cheetah":4]
 
 
if(legs4.isEmpty)
{
    print("Didn't have Data")
}
else
{
    print("had Data")
    
    legs3["snake"] = 10
    
    print(legs3)
}
 
 
var legs5:[String:String] = ["YYZ":"Toronto","DUB":"Dublin",
"DUB2":"Dublin2"]
 
print(legs5)
 
for (legValue, legType) in legs5{
    print("\(legValue): \(legType)")
}

written in full as :

Dictionary<Key, Value>

Creating an Empty Dictionary as :

var nameOfIntegers =[Int:String] ()

var nameOfIntegers:[Int:String] = [:]