Backtracking

• 🟨 17. Letter Combinations of a Phone Number
• 🟨 22. Generate Parentheses
• 🟥 37. Sudoku Solver
• 🟨 39. Combination Sum [Solution]
• 🟨 40. Combination Sum II [Solution]
• 🟨 46. Permutations [Solution]
• 🟨 47. Permutations II
• 🟥 51. N-Queens
• 🟥 52. N-Queens II
• 🟨 77. Combinations [Solution]
• 🟨 78. Subsets
• 🟨 79. Word Search [Solution]
• 🟨 90. Subsets II
• 🟥 212. Word Search II [Solution]