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

s t
s t
949 Points

Help with swift challenge please

Hi All,

I will be really appreciative of some advice on the below challenge please. although I felt like I had grasped the the lesson on the video, I'm completely lost with the task...

In the editor we have a dictionary that contains a three letter country code as a key and that country's capital city as the associated value.

We also have three empty arrays, europeanCapitals, asianCapitals, and otherCapitals. The goal is to iterate through the dictionary and end up with just the names of the capital cities in the relevant array.

For example, after you execute the code you write, europeanCapitals will have the values ["Vaduz", "Brussels", "Sofia"] (not necessarily in that order).

To do this you're going to use a switch statement and switch on the key. For cases where the key is a European country, append the value (not the key!) to the europeanCapitals array. For keys that are Asian countries, append the value to asianCapitals and finally for the default case, append the values to otherCapitals.

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

    // End code

4 Answers

So you just need to check each key and append the value. For example if we need to append the name of each pet to an array of the pets type we would:

for (key, value) in pets {
    switch key {
    case "Boxer", "Beagle", "Chihuahua":
    case "Ragdoll", "Siamese":
s t
s t
949 Points

Hi Brandon,

I figured it out, not quite sure how but the penny dropped and I completed the task correctly.

Thanks for your advice,


No problem.

s t
s t
949 Points

Hi Brandon,

thanks ever so much for your time and help so far. However I'm still stuck...

with regards to for (key, Value) in world... how do I name key and value and amend to that value when the keys & Values are currently listed under the constant world?

am I require to differentiate between key and value when I'm inputting the syntax after "for"?

I'm probably not making much sense so if I need to re-explain myself please let me know.

Thanks again,

Kind regards Steven

Otto linden
Otto linden
5,857 Points

Hi Steve! Im not sure what you mean by the last comment. Can you explain to me what you mean! 🙂// Otto