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

Posted by Aiden Mitchell
Aiden Mitchell
5,572 Points

I don't understand. Please help.

I don't get it at all. Could someone answer this code challenge please?

operators.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 airportCodes {
      case "BEL": europeanCapitals.append(key)
    }
    // End code
}

1 Answer

swiftfun
swiftfun
4,039 Points

Hi Aiden,

I see you started fine by using a Switch statement and properly appending the values (airport names) to a corresponding array.

However you have missed two fundamentals.

1- While using Switch statements you can switch multiple conditions using comma. In this case you must switch every other airport code belonging to the same array:

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

2- Last but not least, all Switch statements must contain a default value to cover any values that are not addressed explicitly in previous cases (MEX, USA, etc...):

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

Hope this is now clear for you.

Aiden Mitchell
Aiden Mitchell
5,572 Points

Thank you!