backtracking

Letter Combinations of a Phone Number

Generate all letter combinations a digit string can represent using backtracking with pruning, leveraging hash table map…

Generate Parentheses

Generate Parentheses requires generating all valid combinations of parentheses with given pairs using backtracking and s…

Sudoku Solver

Solve the Sudoku puzzle by filling empty cells while respecting Sudoku's rules using array scanning and backtracking.

Combination Sum

Find all unique combinations of numbers from a distinct array that sum to a target using controlled backtracking search.

Combination Sum II

Find all unique combinations of numbers that sum to a target using backtracking with careful pruning to avoid duplicates…

Permutations

Generate all possible orderings of a distinct integer array using backtracking search with careful pruning to avoid dupl…

Permutations II

Generate all unique permutations of an array containing duplicates using backtracking and pruning to avoid repeated sequ…

N-Queens

Solve the N-Queens problem using backtracking with pruning, exploring all valid board placements while avoiding conflict…

N-Queens II

Solve the N-Queens II problem using backtracking with pruning to efficiently count all valid placements for n queens on …

Combinations

Generate all combinations of k numbers from the range [1, n] using backtracking and pruning.

Subsets

Generate all subsets of a set of unique integers using backtracking with pruning to avoid duplicates.

Word Search

Solve Word Search with backtracking by exploring adjacent cells to match a target word in a grid.

Gray Code

Generate an n-bit Gray Code sequence using backtracking with pruning and bit manipulation techniques.

Subsets II

Subsets II problem asks to generate unique subsets from an array with possible duplicates using backtracking search with…

Restore IP Addresses

Restore all valid IP addresses from a string using backtracking with pruning, avoiding invalid segments or leading zeros…

Unique Binary Search Trees II

Generate all structurally unique BSTs with values 1 to n using backtracking and recursive tree construction techniques.

Path Sum II

Find all root-to-leaf paths in a binary tree where the sum of node values equals a given target using DFS backtracking.

Word Ladder II

Find all shortest transformation sequences from beginWord to endWord using a dictionary, leveraging backtracking search …

Palindrome Partitioning

Find all possible palindrome partitioning of a string using backtracking and dynamic programming.

Word Break II

Given a string and dictionary, return all possible sentences by adding spaces where each word is in the dictionary.

Word Search II

Solve the Word Search II problem using backtracking with pruning to find all words on a board of characters.

Combination Sum III

Find all unique combinations of k numbers adding to n using efficient backtracking with pruning in arrays.

Binary Tree Paths

Find all root-to-leaf paths in a binary tree using DFS and backtracking, constructing strings for each complete path eff…

Expression Add Operators

Expression Add Operators is solved with backtracking that builds multi-digit operands and tracks multiplication preceden…