In computer science, a Set is a data structure that stores a collection of unique elements. It is typically implemented as an unordered list of elements, where each element can only appear once. Sets are useful for a variety of applications, such as removing duplicates from a list, checking for membership of an element, and performing set operations such as union, intersection, and difference. Sets can be implemented using various data structures, such as hash tables, binary search trees, or arrays. Keep reading below to learn how to use a Set in C#.

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How to use a Set in C# with example code

A Set is a collection of unique elements in C#. It is similar to a List, but it does not allow duplicates. This can be useful in situations where you need to keep track of a list of items, but you don’t want any duplicates.

To use a Set in C#, you first need to include the System.Collections.Generic namespace. You can then create a new Set using the following code:

var mySet = new HashSet<T>();

In this code, T is the type of element that you want to store in the Set. For example, if you want to store a set of integers, you would use the following code:

var mySet = new HashSet<int>();

Once you have created a Set, you can add elements to it using the Add method:


You can also remove elements from the Set using the Remove method:


To check if an element is in the Set, you can use the Contains method:

if (mySet.Contains(1))

Sets also have a number of other useful methods, such as Union, Intersect, and Except, which allow you to perform set operations on two or more sets.

In summary, Sets are a useful collection type in C# that allow you to store a collection of unique elements. They can be created using the HashSet class, and have a number of useful methods for performing set operations.

What is a Set in C#?

In conclusion, a Set in C# is a collection of unique elements that can be used to store and manipulate data in a variety of ways. Sets are useful for a wide range of programming tasks, from simple data storage to complex algorithms and data analysis. With their ability to quickly and efficiently search for and retrieve specific elements, sets are an essential tool for any C# programmer. Whether you are working on a small project or a large-scale application, understanding the basics of sets in C# is an important step towards becoming a skilled and successful programmer.

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