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

Posted by Cameron D
Cameron D
426 Points

I don't understand how to get this code challenge right for Collections and Control Flow

It is the one where you have to make a switch statement involving cities and airports. i tried to put europeanCapitals.append(1) //like an array but it isnt (String: String) format

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 world {
    case "BEL": europeanCapitals.append("Brussels")
    case "LIE": europeanCapitals.append("Vaduz")
    case "BGR": europeanCapitals.append("Sofia")
    case "USA": otherCapitals.append("Washington D.C.")
    case "MEX": otherCapitals.append("Mexico City")
    case "BRA": otherCapitals.append("Brasilia")
    case "IND": asianCapitals.append("New Delhi")
    case "VNM": asianCapitals.append("Hanoi")
    }
    // End code
}

1 Answer

David Papandrew
David Papandrew
8,386 Points
David Papandrew
David Papandrew
8,386 Points

You want to switch on the key value from the world array. So you would write the switch statement differently (see below).

Also, you can reduce the number of case statements with the use of a comma (it's great if you are lazy like me!)

Lastly, you want to append the key's value rather than hard code it in the append argument (again see below as it's easier to understand once you look at the code).

Here's the corrected code:

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 "BEL", "BGR": europeanCapitals.append(value)
    case "IND", "VNM": asianCapitals.append(value)
    default: otherCapitals.append(value)
    }
}
Cameron D
Cameron D
426 Points

Thank you! It makes much more sense now.