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

Sebastian Fernandez
Sebastian Fernandez
2,413 Points
Posted by Sebastian Fernandez
Sebastian Fernandez
2,413 Points

Hi a dont understand the exercise? Help pls

If I put the code in xcode I get an error, why?

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

Mitch Little
Mitch Little
11,870 Points

Hi Sebastian,

You have been asked to use a switch statement with in the for in loop to pattern match on the keys. For each key, the value is assigned to its matching variable

    switch key {
      case "BEL", "LIE", "BGR": europeanCapitals.append(value)
      case "New Dehli", "Hanoi": asianCapitals.append(value)
      default: otherCapitals.append(value)
    }

In simpler terms, the for in loop goes through each key / value pair in the 'world' dictionary. For each key, the switch statement appends the correct value to its matching variable using the .append() method.

I hope this makes sense to you.

All the best,

Mitch