Graphs line
Backtracking problems
Build an answer one choice at a time, and undo the last choice when it leads nowhere. It lists every subset, ordering or placement that fits the rules.
- 9 medium
- 1 hard
The 10 problems
In the order the app teaches them. Each page has the problem, five hints and the explained solution.
- Generate ParenthesesMedium
- SubsetsMedium
- Combination SumMedium
- PermutationsMedium
- Subsets IIMedium
- Combination Sum IIMedium
- Word SearchMedium
- Palindrome PartitioningMedium
- Letter Combinations of a Phone NumberMedium
- N QueensHard
On the roadmap
Backtracking is a station on the graphs line. It builds on Trees. Next comes Graphs and 1-D Dynamic Programming.
The roadmap says why each line runs in its order.
Patterns
One pattern solves these problems. Naming them gives the problems’ methods away, so the list is folded.
Show it
- Backtracking10 problems