You have a list of integers with duplicates: List nums = new List {1, 2, 2, 3, 4, 4, 4, 5};

var unique = new HashSet(nums);

var unique = new HashSet(); unique.Add(nums);

var unique = new HashSet(); foreach(var n in nums) unique = n;

var unique = new HashSet(); unique.AddRange(nums);

You have a list of integers with duplicates: List nums = new List {1, 2, 2, 3, 4, 4, 4, 5};

Solution:Step 1: Understand HashSet constructorHashSet has a constructor that accepts an IEnumerable<T> to initialize with unique elements.Step 2: Analyze each optionvar unique = new HashSet(nums); correctly passes the list to the constructor. var unique = new HashSet(); unique.Add(nums); trie

[Solved] You have a list of integers with duplicates: List<int> nums = new List<int> {1, 2, 2, 3, 4, 4, 4, 5};Which code snippet correctly creates a HashSet<int> containing only the unique elements from nums? | C Sharp (C#)

C Sharp (C#) - Collections

You have a list of integers with duplicates: List<int> nums = new List<int> {1, 2, 2, 3, 4, 4, 4, 5};
Which code snippet correctly creates a HashSet<int> containing only the unique elements from nums?

Avar unique = new HashSet<int>(nums);

Bvar unique = new HashSet<int>(); unique.Add(nums);

Cvar unique = new HashSet<int>(); foreach(var n in nums) unique = n;

Dvar unique = new HashSet<int>(); unique.AddRange(nums);

Step-by-Step Solution

Solution:

Step 1: Understand HashSet constructor
HashSet has a constructor that accepts an IEnumerable<T> to initialize with unique elements.
Step 2: Analyze each option
var unique = new HashSet(nums); correctly passes the list to the constructor. var unique = new HashSet(); unique.Add(nums); tries to add the whole list as one item (invalid). var unique = new HashSet(); foreach(var n in nums) unique = n; assigns int to HashSet variable (invalid). var unique = new HashSet(); unique.AddRange(nums); uses AddRange which HashSet does not have.
Final Answer:
var unique = new HashSet(nums); -> Option A
Quick Check:
Use constructor with collection for unique set [OK]

Quick Trick: Pass list to HashSet constructor for unique items [OK]

Common Mistakes:

MISTAKES

Using Add to add whole list at once
Trying to assign int to HashSet variable
Using AddRange which HashSet lacks

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More C Sharp (C#) Quizzes

You have a list of integers with duplicates: List<int> nums = new List<int> {1, 2, 2, 3, 4, 4, 4, 5};

Step 1: Understand HashSet constructor

Step 2: Analyze each option

Final Answer:

Quick Check:

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