Skip to main content
DifficultyTopic6 of 6
No.ProblemDifficultyFrequency
2603Collect Coins in a Tree
Tree
Hard
100.0%
1742Maximum Number of Balls in a Box
Math
Easy
100.0%
20Valid Parentheses
Stack/Queue
Easy
75.0%
200Number of Islands
GraphMath
Medium
75.0%
155Min Stack
Stack/Queue
Medium
62.5%
236Lowest Common Ancestor of a Binary Tree
Tree
Medium
62.5%