Collection is one of the most important topics for Java programming. Without the proper knowledge of every collection type in Java, it becomes difficult for you to decide which option to pick in a particular scenario.

This course will give you a great understanding of all collection types available in the Collections Framework like lists, linked lists, sets, and hashmaps. 

After completing this course, you will know how data can be modified within a collection, how to sort a collection, and how it can be made thread-safe. You will also cover the internal working of each Java collection so you can work with them more efficiently.

Collections in Java

## Problem 1: Numbers greater than 50

Given an array of numbers, find all the numbers that are greater than 50.

## Solution

There is a `tailSet(E e)` method in the **TreeSet** class that returns a set of all the elements that are greater than the provided element. We will add all the elements from the array to a **TreeSet**. Then we will find all the elements greater than 50 using the `tailSet()` method.

# Problem 1: Numbers greater than 50

Given an array of numbers, find all the numbers that are greater than 50.

# Solution

There is a `tailSet(E e)` method in the **TreeSet** class that returns a set of all the elements that are greater than the provided element. We will add all the elements from the array to a **TreeSet**. Then we will find all the elements greater than 50 using the `tailSet()` method.

Let's look at the solution of TreeSet exercises.

Let's Begin

Lists in Java

LinkedList in Java

CopyOnWriteArrayList in Java

Sets in Java

TreeSet in Java

HashMap In Java

TreeMap in Java

LinkedHashMap in Java

Additional Map Implementations

Arrays Class

Collections Class

TreeSet Exercise Solution

Problem 1: Numbers greater than 50

Solution