Backtracking • Intermediate • 25 min
Word Search
How to explore paths in a grid, mark the current choice, and undo that choice on the way back.
Challenges · Backtracking
Practice problems with walkthroughs, hints, and solutions.
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Backtracking • Intermediate • 20 min
Generate Parentheses
How to use counter-based backtracking to prune invalid prefixes before they turn into wasted work.
Backtracking • Intermediate • 20 min
Combination Sum
How to use controlled [backtracking](/glossary/backtracking) to build unique combinations in canonical order.