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iOS Swift 2.0 Collections and Control Flow Control Flow With Conditional Statements Working with Switch Statements

Diego Valenzuela
Diego Valenzuela
528 Points
Posted by Diego Valenzuela
Diego Valenzuela
528 Points

Inserting values into an array from a dictionary

When in the loop I write : anArray.append(world["BEL"])

"BEL" is the "key" for "Brussels" and it doesn't let me add this value to the array. Take a look at my code and please help me. Thank you.

switch.swift 
var europeanCapitals: [String] = []
var asianCapitals: [String] = []
var otherCapitals: [String] = []

let world = [
  "BEL": "Brussels", 
  "LIE": "Vaduz", 
  "BGR": "Sofia", 
  "USA": "Washington D.C.", 
  "MEX": "Mexico City", 
  "BRA": "Brasilia", 
  "IND": "New Delhi", 
  "VNM": "Hanoi"]

for (key, value) in world {
    // Enter your code below
    switch world {
        case "BEL": europeanCapitals.append(world["BEL"])
        case "LIE": europeanCapitals.append(world["LIE"])
        case "BGR": europeanCapitals.append(world["BGR"])
        case "USA": otherCapitals.append(world["USA"])
        case "MEX": otherCapitals.append(world["MEX"])
        case "BRA": otherCapitals.append(world["BRA"])
        case "IND": asianCapitals.append(world["IND"]) 
        case "VNM": asianCapitals.append(world["VNM"])
        default: print("I dont know what to do")
    }
    // End code
}
Florian Laplanche
Florian Laplanche
4,476 Points
Florian Laplanche
Florian Laplanche
4,476 Points

First, theres a much easier way to use the switch statement, you can combine case by separating them with a comma so you can get all the european capitals and so on in one line. Next, the way i did this challenge was to switch on the key then append the value to the array. This is how I did it. Hope this helps

    switch key {
        case "BEL", "LIE", "BGR": europeanCapitals.append(value)
        case "VNM", "IND": asianCapitals.append(value)
    default: otherCapitals.append(value)
    }

1 Answer

Digvijay Jaiswal
Digvijay Jaiswal
5,565 Points
Digvijay Jaiswal
Digvijay Jaiswal
5,565 Points

Hi, when you are using loop, for ..... in world you are already passing all the value of world in (key, value) so dont use while comparing the case and pass world in it again. eg(case "LIE": europeanCapitals.append(world["LIE"])) Try the code below for reference. Hope that helps. let me know if you need further assistance.

```var europeanCapitals: [String] = [] var asianCapitals: [String] = [] var otherCapitals: [String] = []

let world = [ "BEL": "Brussels", "LIE": "Vaduz", "BGR": "Sofia", "USA": "Washington D.C.", "MEX": "Mexico City", "BRA": "Brasilia", "IND": "New Delhi", "VNM": "Hanoi" ]

for (key, value) in world {

switch key{
    case "LIE","BGR","BEL": print ("The europeanCapitals are: \(value)", europeanCapitals.append(value)) 
    case "VNM", "IND": print ("The asianCapitals are: \(value)", asianCapitals.append(value))
default: print ("The otherCapitals are" , "\(value)", otherCapitals.append(value))
}}