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iOS Swift 2.0 Collections and Control Flow Control Flow With Conditional Statements Working with Switch Statements

Posted by MUZ141061 Shadreck Chawada
MUZ141061 Shadreck Chawada
3,936 Points

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,

Here we have a dictionary of type [String: String] 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.

I've already set up the for in loop for you so jump right in!

2 Answers

Steve Hunter
Steve Hunter
57,712 Points

Hi Shadreck,

As the question says, you need to write a switch/case statement to divide the entries in the world dictionary into three arrays, depending on their key.

The key/value pair is passed into the for loop; the loop iterates through the dictionary one record at a time. At each pass, you need to switch on the key and send the value to the right array. 

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

So, here, we are switching on the key and sending the value associated with the keys "BGR", "LIE" and "BEL" to europeanCapitals. A similar opertaion occurs with all the other keys as they are passed in.

I hope that helps.

Steve.

MUZ141061 Shadreck Chawada
MUZ141061 Shadreck Chawada
3,936 Points
MUZ141061 Shadreck Chawada
MUZ141061 Shadreck Chawada
3,936 Points

thus helpful thanks