Find Size of a List or Set in C#

This post will discuss how to find the size of a List or Set in C#.

1. Using `Count` Property

The standard solution to find the total number of elements in a List or Set is using its Count property. It returns the number of elements that are contained in the collection in O(1) time. The following example demonstrates its usage for a HashSet:

using System;

using System.Collections.Generic;

public class Example

{

public static void Main()

{

HashSet<int> numbers = new HashSet<int>() { 1, 2, 3, 4 };

int size = numbers.Count;

Console.WriteLine(size); // 4

}

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2. Using `Count()` Method

Alternatively, you can invoke LINQ’s Count() method on a collection to determine its size. The following code example demonstrates the usage of Count() method to count the elements in a HashSet.

using System;

using System.Linq;

using System.Collections.Generic;

public class Example

{

public static void Main()

{

HashSet<int> numbers = new HashSet<int>() { 1, 2, 3, 4 };

int size = numbers.Count();

Console.WriteLine(size); // 4

}

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That’s all about finding the size of a List or Set in C#.

Find Size of a List or Set in C#

1. Using Count Property

2. Using Count() Method

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1. Using `Count` Property

2. Using `Count()` Method