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Dashboard
Patterns
Review
Mock
Python
← patterns
01
Arrays & Hashing
when this fires
O(1) lookups, dedupe, or counting frequencies
Study
Guided
Wrestle
Solo
Easy
Medium
Hard
Unsolved only
✓
Two Sum
E
STUDY
✓
Contains Duplicate
E
STUDY
✓
Valid Anagram
E
10 MIN
✓
Group Anagrams
M
30 MIN
✓
Top K Frequent Elements
M
NO NET