LeetCode 242 ·
Easy
Valid Anagram
Given two strings, return true if one is an anagram of the other.
Try it
Step through the core mechanic. The simulator below runs the hash map shape this problem is built on.
Walk the pattern
No dedicated step-through for this one yet. The shape is Hash map — its pattern page has the interactive walkthrough, the reference implementation, and a five-problem progression that this problem sits inside.
The approach
Count characters of the first string in a 26-int array; decrement for the second. All-zero counts means an anagram. Length mismatch is an instant false.
| Aspect | Value |
|---|---|
| Pattern | Hash map |
| Recognise it by | Same multiset of characters. |
| Time complexity | O(n) |
| Space complexity | O(1) |
| Difficulty | Easy |
Who asks it
Companies known to ask this problem, from public LeetCode company-tag aggregations. A signal of where to expect it, not a guarantee.