Algorithm Atlas

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Learn Backtracking with visual DSA lessons

Learn Backtracking with 4 DSA patterns and 24 visual lessons. Follow step-by-step animations and synced C#, Python, and Java code.

Backtracking chooses, explores, and undoes when a path fails.

Choice-Based Backtracking

Generate subsets, combinations, permutations, and partitions by exploring choices.

Subsets Medium · Live decision tree
Subsets II Medium · Live decision tree
Combination Sum Medium · Live decision tree
Combination Sum II Medium · Live decision tree
Permutations Medium · Live decision tree
Permutations II Medium · Live decision tree
Generate Parentheses Medium · Live decision tree
Palindrome Partitioning Medium · Live decision tree
Restore IP Addresses Medium · Live decision tree

Constraint-Based Backtracking

Build answers while rejecting choices that break a rule.

Graph Coloring (M-Coloring Problem) Medium · Live decision tree
Knight’s Tour Medium · Live decision tree
Partition to K Equal Sum Subsets Medium · Live decision tree
Matchsticks to Square Medium · Live decision tree
N-Queens Hard · Live decision tree
N-Queens II Hard · Live decision tree

Grid / Path Backtracking

Move through a grid, mark the current path, and undo marks while returning.

Rat in a Maze Medium · Live decision tree
Path with Maximum Gold Medium · Live decision tree
Sudoku Solver Hard · Live decision tree
Word Search II Hard · Live decision tree
Unique Paths III Hard · Live decision tree

Decision Tree / Sequence Generation

Generate complete strings or structures by extending one prefix at a time.

Letter Combinations of a Phone Number Medium · Live decision tree
All possible Full binary Trees Medium · Live decision tree
Expression Add Operators Hard · Live decision tree
Word Break 2 Hard · Live decision tree