PROBLEMS/BACKTRACKING
Backtracking LeetCode Problems
80 hand-tagged Backtracking problems across 5 interview patterns (Permutations, Combinations / Subsets, Constraint Satisfaction (N-Queens), String Partitioning (Palindrome Partitioning), Path Finding with Backtracking), ranked by importance (how often each pattern shows up in real coding interviews). Work top-down within each pattern.
| # | PROBLEM | DIFF | ELO | IMP | PATTERNS |
|---|---|---|---|---|---|
| 1 | Permutations | Easy | 1244 | 92 | Frequency Counting / Hash Map Lookup |
| 2 | Permutations II | Medium | 1408 | 82 | Frequency Counting / Hash Map Lookup · Sorting + Comparison |
| 3 | Letter Tile Possibilities | Medium | 1741 | 72 | Frequency Counting / Hash Map Lookup |
| 4 | Permutations IIIPREMIUM | Easy | 1380 | 58 | Constraint Satisfaction (N-Queens) |
| 5 | Palindrome Permutation IIPREMIUM | Medium | 1558 | 50 | Frequency Counting / Hash Map Lookup |
| # | PROBLEM | DIFF | ELO | IMP | PATTERNS |
|---|---|---|---|---|---|
| 1 | Subsets | Easy | 1211 | 92 | General Bit Manipulation |
| 2 | Combination Sum | Easy | 1317 | 90 | Unbounded Knapsack |
| 3 | Combinations | Easy | 1258 | 88 | |
| 4 | Generate Parentheses | Easy | 1375 | 85 | Linear Recurrence DP |
| 5 | Subsets II | Easy | 1361 | 84 | Sorting + Comparison |
| # | PROBLEM | DIFF | ELO | IMP | PATTERNS |
|---|---|---|---|---|---|
| 1 | N-Queens | Medium | 1697 | 82 | Matrix Traversal (Diagonal, Valid Sudoku, etc) |
| 2 | N-Queens II | Medium | 1667 | 68 | General Bit Manipulation |
| 3 | Sudoku Solver | Hard | 1872 | 62 | Matrix Traversal (Diagonal, Valid Sudoku, etc) |
| 4 | Construct the Lexicographically Largest Valid Sequence | Hard | 2080 | 45 | General Greedy (Greedy is main insight) |
| 5 | Flip Game IIPREMIUM | Medium | 1768 | 38 | Linear Recurrence DP · General Math |
| # | PROBLEM | DIFF | ELO | IMP | PATTERNS |
|---|---|---|---|---|---|
| 1 | Palindrome Partitioning | Medium | 1548 | 85 | Word Break / String DP |
| 2 | Restore IP Addresses | Medium | 1460 | 55 | Constraint Satisfaction (N-Queens) |
| 3 | Expression Add Operators | Hard | 2088 | 53 | General Math · Frequency Counting / Hash Map Lookup |
| 4 | Word Pattern IIPREMIUM | Medium | 1712 | 47 | Frequency Counting / Hash Map Lookup |
| 5 | Find the Punishment Number of an Integer | Medium | 1679 | 45 | General Math |
| # | PROBLEM | DIFF | ELO | IMP | PATTERNS |
|---|---|---|---|---|---|
| 1 | Word Search | Medium | 1457 | 87 | Matrix Traversal (Diagonal, Valid Sudoku, etc) |
| 2 | Path with Maximum Gold | Medium | 1663 | 68 | Matrix Traversal (Diagonal, Valid Sudoku, etc) |
| 3 | All Paths From Source to Target | Easy | 1383 | 62 | DFS Path Finding |
| 4 | Robot Room CleanerPREMIUM | Hard | 2087 | 53 | DFS Connected Components |
| 5 | Unique Paths III | Hard | 1830 | 52 | Bitmask DP |
EVERY PATTERN
// your mastery
What's your Backtracking tier?
leaps.gg syncs your LeetCode history and scores your mastery of every pattern, then recommends the exact problems to do next with spaced repetition. Free to start.
GET MY MASTERY MAP →