import java.util.*;

// A brief review of how to use, iterate through, and
// remove from sets/maps.
public class SetMapReview {
  public static void main(String[] args) {
    // Create a set of Strings, add some names
    Set<String> colors = new HashSet<String>();
    colors.add("red");
    colors.add("yellow");
    colors.add("blue");
    colors.add("orange");
    colors.add("new blue");

    // Print out each string on its own line
    // Iterator:
    //    hasNext
    //    next
    //    remove
    Iterator<String> colorsIt = colors.iterator();
    while (colorsIt.hasNext()) {
      String color = colorsIt.next();
      System.out.println(color);  
    }
    System.out.println();
    System.out.println();

    // Remove strings starting with 'o'
    Iterator<String> otherIt = colors.iterator();
    while (otherIt.hasNext()) {
      String color = otherIt.next();
      if (color.startsWith("o")) {
        otherIt.remove();
      } 
    }

    // print out what the set now contains
    for (String color : colors) {
      System.out.println(color);
    }

    // Create a map of the strings to their length.
    // HashMap<E> : unsorted, but way faster
    // TreeMap<E> : sorted
    Map<String, Integer> lengths = new HashMap<String, Integer>();
    for (String color : colors) {
      lengths.put(color, color.length());
    }
    System.out.println();
    System.out.println();

    // Print out each mapping of name to its length
    //System.out.println(lengths);

    for (String color : lengths.keySet()) {
      System.out.println("The length of " + color + " is..." + lengths.get(color));
    }
    System.out.println();
    System.out.println();

    // of type Set<String>
    System.out.println("Keys in my map: " + lengths.keySet());
  }
}