LeetCode Topics

Tree

Problem Name	Difficulty
0101-symmetric-tree	Easy
0104-maximum-depth-of-binary-tree	Easy
0111-minimum-depth-of-binary-tree	Easy
0112-path-sum	Easy
0226-invert-binary-tree	Easy
0404-sum-of-left-leaves	Easy

Depth-First Search

Problem Name	Difficulty
0101-symmetric-tree	Easy
0104-maximum-depth-of-binary-tree	Easy
0111-minimum-depth-of-binary-tree	Easy
0112-path-sum	Easy
0226-invert-binary-tree	Easy
0404-sum-of-left-leaves	Easy

Breadth-First Search

Problem Name	Difficulty
0101-symmetric-tree	Easy
0104-maximum-depth-of-binary-tree	Easy
0111-minimum-depth-of-binary-tree	Easy
0112-path-sum	Easy
0226-invert-binary-tree	Easy
0404-sum-of-left-leaves	Easy

Binary Tree

Problem Name	Difficulty
0101-symmetric-tree	Easy
0104-maximum-depth-of-binary-tree	Easy
0111-minimum-depth-of-binary-tree	Easy
0112-path-sum	Easy
0226-invert-binary-tree	Easy
0404-sum-of-left-leaves	Easy

Two Pointers

Problem Name	Difficulty
0005-longest-palindromic-substring	Medium
0125-valid-palindrome	Easy
0167-two-sum-ii-input-array-is-sorted	Medium
0283-move-zeroes	Easy
1768-merge-strings-alternately	Easy

String

Problem Name	Difficulty
0005-longest-palindromic-substring	Medium
0020-valid-parentheses	Easy
0049-group-anagrams	Medium
0125-valid-palindrome	Easy
0242-valid-anagram	Easy
1071-greatest-common-divisor-of-strings	Easy
1768-merge-strings-alternately	Easy

Math

Problem Name	Difficulty
1071-greatest-common-divisor-of-strings	Easy

Array

Problem Name	Difficulty
0001-two-sum	Easy
0046-permutations	Medium
0049-group-anagrams	Medium
0167-two-sum-ii-input-array-is-sorted	Medium
0217-contains-duplicate	Easy
0283-move-zeroes	Easy
1431-kids-with-the-greatest-number-of-candies	Easy

Hash Table

Problem Name	Difficulty
0001-two-sum	Easy
0049-group-anagrams	Medium
0217-contains-duplicate	Easy
0242-valid-anagram	Easy

Sorting

Problem Name	Difficulty
0049-group-anagrams	Medium
0217-contains-duplicate	Easy
0242-valid-anagram	Easy

Stack

Problem Name	Difficulty
0020-valid-parentheses	Easy

Bracket Sequences

Problem Name	Difficulty
0020-valid-parentheses	Easy

Dynamic Programming

Problem Name	Difficulty
0005-longest-palindromic-substring	Medium

Manacher

Problem Name	Difficulty
0005-longest-palindromic-substring	Medium

Backtracking

Problem Name	Difficulty
0046-permutations	Medium

Binary Search

Problem Name	Difficulty
0167-two-sum-ii-input-array-is-sorted	Medium