leetcode

Binary Tree

Problem	Difficulty	Solution
Add One Row to Tree	Medium	add_one_row.py
Average of Levels in Binary Tree	Easy	average_of_levels.py
Balanced Binary Tree	Easy	is_balanced.py
Binary Search Tree Iterator	Medium	bst_iterator.py
Binary Tree Inorder Traversal	Easy	inorder_traversal.py
Binary Tree Level Order Traversal	Medium	level_order.py
Binary Tree Postorder Traversal	Easy	postorder_traversal.py
Binary Tree Preorder Traversal	Easy	preorder_traversal.py
Binary Tree Right Side View	Medium	right_side_view.py
Construct Binary Tree from Inorder and Postorder Traversal	Medium	build_tree2.py
Construct Binary Tree from Preorder and Inorder Traversal	Medium	build_tree1.py
Construct Sorted Array to Binary Search Tree	Medium	sorted_array2BST.py
Convert Sorted List to Binary Search Tree	Medium	sorted_list2BST.py
Delete Node in a Binary Search Tree	Medium	delete_node.py
Find Largest Values in Each Tree Row	Medium	largest_values
Flatten Binary Tree To Linked List	Medium	flatten.py
Insert into a Binary Search Tree	Medium	insert_intoBST.py
Invert Binary Tree	Easy	invert_tree
Kth Smallest Element in a Binary Search Tree	Medium	kth_smallest.py
Lowest Common Ancestor of a Binary Tree	Medium	lowest_common_ancestor.py
Maximum Depth of Binary Tree	Easy	max_depth.py
Minimum Depth of Binary Tree	Easy	min_depth.py
Most Frequent Subtree Sum	Medium	find_frequent_tree_sum.py
Path Sum I	Medium	has_path_sum.py
Path Sum II	Medium	path_sum.py
Path Sum III	Medium	path_sum2.py
Recover Binary Search Tree	Medium	recover_tree.py
Same Tree	Easy	is_same_tree.py
Search in a Binary Search Tree	Easy	searchBST.py
Serialize and Deserialize Binary Tree	Hard	codec.py
Symmetric Tree	Easy	is_symmetric.py
Validate Binary Search Tree	Medium	is_validBST.py

Linked List

Problem	Difficulty	Solution
Convert a Binary Number in a Linked List to Integer	Easy	get_decimal_value.py
Delete the Middle Node of a Linked List	Medium	delete_middle.py
Design Circular Queue	Medium	circular_queue.py
Insert Greatest Common Divisors in Linked List	Medium	insert_greatest_common_divisors.py
Intersection of Two Linked Lists	Easy	get_intersection_node.py
Linked List Cycle	Easy	has_cycle.py
Linked List Cycle II	Medium	detect_cycle.py
LRU Cache	Medium	lru_cache.py
Merge K Sorted Lists	Hard	merge_k_lists.py
Merge Two Sorted Lists	Easy	merge_two_lists.py
Middle of Linked List	Easy	middle_node.py
Odd Even Linked List	Medium	odd_even_list.py
Palindrome Linked List	Easy	is_palindrome.py
Remove Elements	Easy	remove_elements.py
Remove Nth Node from End of List	Medium	remove_nth_from_end.py
Remove Duplicates from Sorted List	Easy	remove_duplicates.py
Remove Zero Sum Consecutive Nodes from Linked List	Medium	remove_zero_sum_sublists.py
Reverse Linked List	Easy	reverse_list.py
Remove Nodes in Even Length Groups	Medium	remove_even_length_groups.py
Sort List	Medium	sort_list.py
Split Linked List in Parts	Medium	split_list_to_parts.py
Next Greater Node in Linked List	Medium	next_larger_nodes.py

Priority Queue

Problem	Difficulty	Solution
Find Subsequence of Length K With the Largest Sum	Easy	max_subsequence.py
Kth Largest Element in an Array	Medium	find_kth_largest.py
Kth Largest Element in a Stream	Easy	kth_largest.py
The K Weakest Rows in a Matrix	Easy	k_weakest_row.py
Top K Frequent Words	Medium	top_k_frequent.py

Binary Search

Problem	Difficulty	Solution
Binary Search	Easy	search.py
Find First and Last Position of Element in Sorted Array	Medium	search_range.py
Search in Rotated Sorted Array I	Medium	search_rotated_array.py
Search in Rotated Sorted Array II	Medium	search_rotated_array2.py
Missing Number	Easy	find_missing_number.py

Sliding Window

Problem	Difficulty	Solution
Minimum Size Subarray Sum	Medium	min_sub_array_len.py
Sliding Window Maximum	Hard	max_sliding_window.py
Find the Power of K-Size Subarray I	Medium	results_array.py

Dynamic Programming

Problem	Difficulty	Solution
Coin Change	Medium	coin_change.py
Count Sorted Vowel Strings	Medium	count_vowel_strings.py
Decode Ways	Medium	num_decodings.py
Delete Operation for Two Strings	Medium	min_distance2.py
Edit Distance	Medium	min_distance.py
Fibonacci Number	Easy	fib.py
House Robber I	Medium	rob1.py
House Robber II	Medium	rob2.py
House Robber III	Medium	rob3.py
Integer Break	Medium	integer_break.py
Jump Game I	Medium	can_jump.py
Jump Game II	Medium	jump.py
Longest Increasing Subsequence	Medium	length_of_lis.py
Longest Palindrome	Medium	longest_palindrome.py
Maximal Squares	Medium	maximal_squares.py
Maximum Subarray	Medium	max_sub_array.py
Minimum Path Sum	Medium	min_path_sum.py
Minimum Total	Medium	minimum_total.py
Pascal's Triangle I	Easy	pasacals_triangle1.py
Pascal's Triangle II	Easy	pasacals_triangle2.py
Perfect Squares	Medium	num_sqaures.py
Ugly Number II	Medium	nth_ugly_number.py
Unique Paths I	Medium	unique_paths.py
Unique Paths II	Medium	unique_paths_with_obstacles.py
Wiggle Subsequence	Medium	wiggle_max_length.py

Combinatorics

Problem	Difficulty	Solution
Unique Paths	Medium	unique_paths.py
Count Numbers with Unique Digits	Medium	count_numbers_with_unique_digits.py

Backtrack

Problem	Difficulty	Solution
Beautiful Arrangement	Medium	count_arrangement.py
Combination Sum	Medium	combination_sum.py
Letter Combinations of a Phone Number	Medium	letter_combinations.py
N-Queens I	Hard	solve_n_queens1.py
N-Queens II	Hard	solve_n_queens2.py
Permutations	Medium	permute.py
Subset I	Medium	subset1.py
Subset II	Medium	subset2.py
Sudoku Solver	Hard	solve_sudoku.py