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

I am stuck on this code challenge

I have tried this on a swift playground and it's not working

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 "USA": otherCapitals.append("Washington D.C.")
        case "BGR": europeanCapitals.append("Sofia")
    // End code
    }
}

2 Answers

Jeff McDivitt
Jeff McDivitt
23,970 Points

Hi Brendan - You need to switch on the key not worlds, you also need to append the value and also make sure your have a return case for all values. The other ones should go under .other

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","LIE":
        europeanCapitals.append(value)
    case "IND" :
        asianCapitals.append(value)
    default:
        otherCapitals.append(value)
    }
}
Jack Baer
Jack Baer
5,049 Points

Hello -

There are three problems here:

First off, you are switching on world. Remember, (key, value) is what the current section of world is being assigned to. Meaning, you have to switch either key or value.

Second off, your cases aren't correct. You are only checking if it is USA or BGR. You need to check every key.

Lastly, you didn't add a default clause, which is required.

Your code:

for (key, value) in world { // Enter your code below switch world { case "USA": otherCapitals.append("Washington D.C.") case "BGR": europeanCapitals.append("Sofia") // End code } }

I would highly recommend going back through the section on switching, since everything wrong with your code had to do with your attempt at using the switch statement. Also maybe brush up on for-in loops again since you didn't understand the temporary tuple.

I hope this helps, and if you have any more questions about this, please ask.

~Jack