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

Mark Cai
Mark Cai
1,505 Points
Posted by Mark Cai
Mark Cai
1,505 Points

Code needs to use the unwrap (!) character inorder to run

Direction does not talk about using the unwrap character (!). My code only executes when using the ! character:

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 key { case "BEL": europeanCapitals.append(world["BEL"]!) case "LIE": europeanCapitals.append(world["LIE"]!) case "BGR": europeanCapitals.append(world["BGR"]!) case "IND": asianCapitals.append(world["IND"]!) case "VNM": asianCapitals.append(world["VNM"]!) default: otherCapitals.append(world["VNM"]!) } // End code }

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

    // End code
}

1 Answer

Brent McCoy
PLUS
Brent McCoy
Courses Plus Student 31,764 Points
Brent McCoy
Brent McCoy
Courses Plus Student 31,764 Points

The code is within a for/in loop that uses the temporary variables (key, value) to iterate through the dictionary - so you can use "value" to access the current value for each dictionary key. Also this way you can put multiple keys that need to take the same action within the same case:

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