Average of Levels in Binary Tree

07-19

Triangle

07-16

Third Maximum Number

06-14

Find All Duplicates in an Array

06-13

K-diff Pairs in an Array

06-07

Reshape the Matrix

06-06

Can Place Flowers

06-06

Convert a Number to Hexadecimal

06-02

Convert Sorted Array to Binary Search Tree

05-30

Subtree of Another Tree

05-30