← Roadmapsall recursion & backtracking problems
🧩

Recursion & Backtracking

Subsets, permutations, combinations, grid solving.

4 subtopics · 36 problems0/33 on the path solved
next ▸ Count Subsetsmachine 1050
01

Subsets & combos

0/16 of 19

Subsets, combinations, parentheses, phone letters.

○Count SubsetsSilver · 1050○Combinations (n choose k)Silver · 1100○Count Combinations (n choose k)Silver · 1200○Subsets With DuplicatesGold · 1300○Generate ParenthesesGold · 1300○Count Subsets of Size KGold · 1350○Combination SumGold · 1350○Combination Sum III — CountGold · 1350○Generate All Subsets (Lexicographic)Gold · 1350○Combination Sum IIGold · 1450○Generate Valid ParenthesesGold · 1450○Generate All SubsetsGold · 1500○Combinations N Choose KGold · 1500○Combination Sum (Count)Gold · 1500○Partition to K Equal Sum SubsetsGold · 1540○Generate Balanced ParenthesesGold · 1550+ 3 more in the arena →
02

Permutations

0/6

Permutations, with duplicates.

○Count Permutations of Distinct ItemsSilver · 1100○Letter Case PermutationSilver · 1150○Permutations With DuplicatesGold · 1400○Unique Permutations (Count)Gold · 1500○Generate All PermutationsPlatinum · 1750○Beautiful ArrangementPlatinum · 1750
03

Sum & partition

0/4

Combination sum, palindrome partition, IP.

○Palindrome PartitioningGold · 1500○Restore IP AddressesGold · 1500○Palindrome Partitioning (Count)Gold · 1500○Restore IP Addresses (Count)Gold · 1550
04

Grid & constraints

0/7

N-Queens, sudoku, word search, maze, paths.

○Validate Sudoku BoardGold · 1400○Count Paths Avoiding ObstaclesGold · 1420○Count Grid PathsGold · 1450○Word Search ExistsGold · 1450○Word SearchGold · 1550○Count Grid Paths With ObstaclesPlatinum · 1700○Valid Sudoku BoardPlatinum · 1720