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→Tree (Reduces cost of search, insert and delete)
===With apt===
===With apt===
<nowiki>sudo apt-add-repository ppa:webupd8team/java
<nowiki>sudo apt-add-repository ppa:webupd8team/java
sudo apt-get update
sudo apt-get install oracle-java8-installer</nowiki>
Also ensure your JAVA_HOME variable has been set to:
Also ensure your JAVA_HOME variable has been set to:
</syntaxhighlight>
</syntaxhighlight>
=== Hashing (Fast searches) ===
===Hashing (Fast searches)===
LinkedHashSet: keeps the order in which elements are inserted<syntaxhighlight lang="java">
LinkedHashSet: keeps the order in which elements are inserted<syntaxhighlight lang="java">
Set<Integer> numbers = new LinkedHashSet<>();
Set<Integer> numbers = new LinkedHashSet<>();
numbers.add(4185);
numbers.add(4185);
numbers.add(545);
numbers.add(545);
</syntaxhighlight><br />
</syntaxhighlight><br /><syntaxhighlight lang="java">
<syntaxhighlight lang="java">
import java.util.List;
import java.util.List;
import java.util.Set;
import java.util.Set;
Set<Character> HashSet = new HashSet<>(characters);
Set<Character> HashSet = new HashSet<>(characters);
System.out.println("linkedHashSet" + linkedHashSet);
System.out.println("linkedHashSet" + linkedHashSet);
}
}
</syntaxhighlight>
=== Tree (Reduces cost of search, insert and delete) ===
<syntaxhighlight lang="java">
TreeSet<Integer> numbers = new TreeSet<>(Set.of(65, 54, 34, 12, 99));
numbers.floor(40); // lower or equal to 40 in set
numbers.lower(34); //lower than 34
numbers.ceiling(34); //>=
numbers.higher(34); //>
numbers.subSet(20, 80); // Returns numbers between 20 and 80 in set
</syntaxhighlight>
=== Queue ===
<syntaxhighlight lang="java">
Queue <String> queue = new PriorityQueue<>();
queue.poll() // pull things out of queue
queue.offer("Apple") // put things on queue
queue.addAll(List.of("Zebra", "Monkeky")) // put lists on queue
</syntaxhighlight><syntaxhighlight lang="java">
import java.util.Comparator;
import java.util.List;
import java.util.PriorityQueue;
import java.util.Queue;
class StringLenghtComparator implements Comparator<String> {
@Override
public int compare(String value1, String value2){
return Integer.compare(value1.lenght(), value2.length());
}
}
public class QueueRunner{
public void main(String[]; args){
// Queue<String> queue = new PriorityQueue<>(new StringLenghtComparator ());
Queue<String> queue = new PriorityQueue<>();
queue.addAll(List.of("Zebra", "Monkey", "Cat"));
System.out.println(queue.poll());
}
}
}
}