Interview Question

HashSet vs TreeSet?

HashSet is unordered hashing; TreeSet is sorted tree-based storage.

💡 Concept ✅ Quick Revision ☕ Java

Answer

HashSet is hash-table based; TreeSet is an ordered NavigableSet backed by a tree. • HashSet iteration order is unspecified. • TreeSet orders elements by natural ordering or a Comparator. • HashSet offers average constant-time basic operations; TreeSet offers logarithmic basic operations.

Example

Code

var sorted = new java.util.TreeSet<Integer>();
sorted.add(3); sorted.add(1); sorted.add(2);
System.out.println(sorted);

Output

[1, 2, 3]

Quick Revision

HashSet is unordered hashing; TreeSet is sorted tree-based storage.

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PreviousArrayList vs LinkedList?

NextHashMap vs TreeMap?

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