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D14

Trees

64 stations · 23h

Binary tree traversals, views, LCA and path problems. 64 interview problems explained by codestorywithMIK (23h of video), grouped into 8 patterns such as Traversals (DFS / BFS), Height, Depth & Diameter, Root-to-Leaf Paths.

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problems by zone (pattern)
  • Traversals (DFS / BFS)22
  • Height, Depth & Diameter5
  • Root-to-Leaf Paths7
  • LCA & Ancestors3
  • Construction & Serialization6
  • Tree Modification4
  • Tree as Graph17
  • General Recursion on Trees33

  1. Traversals (DFS / BFS)

    0 of 22 passed
  2. Time Needed to Inform All EmployeesLC 1376 · 24:56
    MediumGoogle · Amazon · +2 more companiesLeetCode ↗ (opens in a new tab)
  3. Binary Tree Right Side ViewLC 199 · 10:45
    MediumGoogle · Amazon · +13 more companiesLeetCode ↗ (opens in a new tab)
  4. Binary Tree Right Side ViewLC 199 · 9:22
    LeetCode ↗ (opens in a new tab)
  5. Construct Binary Tree From Preorder And Inorder TraversalLC 105 · 24:27
    MediumGoogle · Amazon · +8 more companiesLeetCode ↗ (opens in a new tab)
  6. Check Completeness of a Binary Tree (BFS) - (Meta, Amazon) : Explanation ➕ Live CodingLC 958 · 12:51
    MediumGoogle · Amazon · +3 more companiesLeetCode ↗ (opens in a new tab)
  7. Check Completeness of a Binary Tree (DFS) - (Meta, Amazon) : Explanation ➕ Live CodingLC 958 · 12:19
    MediumGoogle · Amazon · +3 more companiesLeetCode ↗ (opens in a new tab)
  8. Binary Tree Preorder Traversal - (Microsoft, Walmart, Flipkart, Amazon) : Explanation ➕ Live Coding2:37
    LeetCode ↗ (opens in a new tab)
  9. Construct Binary Tree from Inorder and Postorder TraversalLC 106 · 25:38
    MediumGoogle · Amazon · +5 more companiesLeetCode ↗ (opens in a new tab)
  10. Longest ZigZag Path in a Binary Tree -LC 1372 · 25:12
    MediumAmazon · MicrosoftLeetCode ↗ (opens in a new tab)
  11. Maximum Width of Binary TreeLC 662 · 16:53
    MediumGoogle · Amazon · +6 more companiesLeetCode ↗ (opens in a new tab)
  12. Maximum Level Sum of a Binary TreeLC 1161 · 20:01
    MediumGoogle · Amazon · +2 more companiesLeetCode ↗ (opens in a new tab)
  13. Validate Binary Tree NodesLC 1361 · 24:42
    MediumGoogle · Meta · +1 more companiesLeetCode ↗ (opens in a new tab)
  14. Find Largest Value in Each Tree RowLC 515 · 22:53
    MediumGoogle · Amazon · +6 more companiesLeetCode ↗ (opens in a new tab)
  15. Binary Tree Inorder TraversalLC 94 · 15:14
    EasyGoogle · Amazon · +5 more companiesLeetCode ↗ (opens in a new tab)
  16. Find Bottom Left Tree ValueLC 513 · 23:52
    MediumGoogle · Amazon · +4 more companiesLeetCode ↗ (opens in a new tab)
  17. Even Odd TreeLC 1609 · 40:37
    MediumAmazon · Meta · +1 more companiesLeetCode ↗ (opens in a new tab)
  18. Cousins in Binary Tree IILC 2641 · 35:35
    MediumGoogle · AmazonLeetCode ↗ (opens in a new tab)
  19. Reverse Odd Levels of Binary TreeLC 2415 · 35:14
    MediumGoogle · josh technologyLeetCode ↗ (opens in a new tab)
  20. Minimum Number of Operations to Sort a Binary Tree by LevelLC 2471 · 24:36
    MediumGoogle · Amazon · +1 more companiesLeetCode ↗ (opens in a new tab)
  21. Find Elements in a Contaminated Binary TreeLC 1261 · 13:03
    MediumGoogle · AmazonLeetCode ↗ (opens in a new tab)
  22. Recover a Tree From Preorder TraversalLC 1028 · 26:46
    HardGoogle · Amazon · +4 more companiesLeetCode ↗ (opens in a new tab)
  23. Construct Binary Tree from Preorder and Postorder TraversalLC 889 · 39:51
    MediumGoogle · Amazon · +4 more companiesLeetCode ↗ (opens in a new tab)

  24. Height, Depth & Diameter

    0 of 5 passed
  25. Binary Tree Maximum Path Sum - (Google, Meta, Amazon, Flipkart) : Explanation ➕ Live CodingLC 124 · 26:35
    HardGoogle · Amazon · +22 more companiesLeetCode ↗ (opens in a new tab)
  26. Minimum Depth of Binary TreeLC 111 · 11:48
    EasyGoogle · Amazon · +4 more companiesLeetCode ↗ (opens in a new tab)
  27. Diameter of Binary TreeLC 543 · 19:38
    EasyGoogle · Amazon · +18 more companiesLeetCode ↗ (opens in a new tab)
  28. Height of Binary Tree After Subtree Removal QueriesLC 2458 · 41:20
    HardGoogle · Meta · +1 more companiesLeetCode ↗ (opens in a new tab)
  29. Balanced Binary TreeLC 110 · 16:45
    EasyGoogle · Amazon · +6 more companiesLeetCode ↗ (opens in a new tab)

  30. Root-to-Leaf Paths

    0 of 7 passed
  31. Path Sum IILC 113 · 12:38
    MediumGoogle · Amazon · +8 more companiesLeetCode ↗ (opens in a new tab)
  32. Path Sum - (Amazon, Microsoft, Accolite, Adobe...) : Explanation + Live Coding 🧑🏻‍💻👩🏻‍💻LC 112 · 10:33
    EasyGoogle · Amazon · +7 more companiesLeetCode ↗ (opens in a new tab)
  33. Binary Tree Maximum Path Sum - (Google, Meta, Amazon, Flipkart) : Explanation ➕ Live CodingLC 124 · 26:35
    HardGoogle · Amazon · +22 more companiesLeetCode ↗ (opens in a new tab)
  34. Sum Root to Leaf NumbersLC 129 · 12:42
    MediumGoogle · Amazon · +5 more companiesLeetCode ↗ (opens in a new tab)
  35. Paths from root with a specified sum11:18
    LeetCode ↗ (opens in a new tab)
  36. Pseudo-Palindromic Paths in a Binary TreeLC 1457 · 26:41
    MediumAmazonLeetCode ↗ (opens in a new tab)
  37. Sum of Root To Leaf Binary NumbersLC 1022 · 14:12
    EasyGoogle · Amazon · +2 more companiesLeetCode ↗ (opens in a new tab)

  38. LCA & Ancestors

    0 of 3 passed
  39. Lowest Common Ancestor of a Binary TreeLC 236 · 16:44
    MediumGoogle · Amazon · +20 more companiesLeetCode ↗ (opens in a new tab)
  40. Maximum Difference Between Node and AncestorLC 1026 · 35:23
    MediumAmazon · Meta · +3 more companiesLeetCode ↗ (opens in a new tab)
  41. Lowest Common Ancestor of Deepest LeavesLC 1123 · 42:25
    MediumGoogle · Amazon · +2 more companiesLeetCode ↗ (opens in a new tab)

  42. Construction & Serialization

    0 of 6 passed
  43. Construct Quad Tree (Leetcode - 427) - (Google) : Explanation ➕ Live CodingLC 427 · 28:36
    MediumGoogle · Amazon · +5 more companiesLeetCode ↗ (opens in a new tab)
  44. Construct Binary Tree From Preorder And Inorder TraversalLC 105 · 24:27
    MediumGoogle · Amazon · +8 more companiesLeetCode ↗ (opens in a new tab)
  45. Construct Binary Tree from Inorder and Postorder TraversalLC 106 · 25:38
    MediumGoogle · Amazon · +5 more companiesLeetCode ↗ (opens in a new tab)
  46. Create Binary Tree From DescriptionsLC 2196 · 19:14
    MediumGoogle · Amazon · +5 more companiesLeetCode ↗ (opens in a new tab)
  47. Recover a Tree From Preorder TraversalLC 1028 · 26:46
    HardGoogle · Amazon · +4 more companiesLeetCode ↗ (opens in a new tab)
  48. Construct Binary Tree from Preorder and Postorder TraversalLC 889 · 39:51
    MediumGoogle · Amazon · +4 more companiesLeetCode ↗ (opens in a new tab)

  49. Tree Modification

    0 of 4 passed
  50. Delete Nodes And Return Forest SolvedLC 1110 · 15:24
    MediumGoogle · Amazon · +2 more companiesLeetCode ↗ (opens in a new tab)
  51. Add One Row to TreeLC 623 · 15:08
    MediumGoogle · BloombergLeetCode ↗ (opens in a new tab)
  52. Delete Leaves With a Given ValueLC 1325 · 12:42
    MediumGoogle · Amazon · +2 more companiesLeetCode ↗ (opens in a new tab)
  53. Flip Equivalent Binary TreesLC 951 · 23:43
    MediumGoogle · Amazon · +1 more companiesLeetCode ↗ (opens in a new tab)

  54. Tree as Graph

    0 of 17 passed
  55. Time Needed to Inform All EmployeesLC 1376 · 24:56
    MediumGoogle · Amazon · +2 more companiesLeetCode ↗ (opens in a new tab)
  56. Check Completeness of a Binary Tree (BFS) - (Meta, Amazon) : Explanation ➕ Live CodingLC 958 · 12:51
    MediumGoogle · Amazon · +3 more companiesLeetCode ↗ (opens in a new tab)
  57. Check Completeness of a Binary Tree (DFS) - (Meta, Amazon) : Explanation ➕ Live CodingLC 958 · 12:19
    MediumGoogle · Amazon · +3 more companiesLeetCode ↗ (opens in a new tab)
  58. Maximum Width of Binary TreeLC 662 · 16:53
    MediumGoogle · Amazon · +6 more companiesLeetCode ↗ (opens in a new tab)
  59. Maximum Level Sum of a Binary TreeLC 1161 · 20:01
    MediumGoogle · Amazon · +2 more companiesLeetCode ↗ (opens in a new tab)
  60. All Nodes Distance K in Binary TreeLC 863 · 21:59
    MediumGoogle · Amazon · +16 more companiesLeetCode ↗ (opens in a new tab)
  61. Validate Binary Tree NodesLC 1361 · 24:42
    MediumGoogle · Meta · +1 more companiesLeetCode ↗ (opens in a new tab)
  62. Find Largest Value in Each Tree RowLC 515 · 22:53
    MediumGoogle · Amazon · +6 more companiesLeetCode ↗ (opens in a new tab)
  63. Amount of Time for Binary Tree to Be InfectedLC 2385 · 29:25
    MediumGoogle · Amazon · +11 more companiesLeetCode ↗ (opens in a new tab)
  64. Amount of Time for Binary Tree to Be InfectedLC 2385 · 41:15
    MediumGoogle · Amazon · +11 more companiesLeetCode ↗ (opens in a new tab)
  65. Count the nodes at distance K from leaf45:50
    LeetCode ↗ (opens in a new tab)
  66. Find Bottom Left Tree ValueLC 513 · 23:52
    MediumGoogle · Amazon · +4 more companiesLeetCode ↗ (opens in a new tab)
  67. Even Odd TreeLC 1609 · 40:37
    MediumAmazon · Meta · +1 more companiesLeetCode ↗ (opens in a new tab)
  68. Cousins in Binary Tree IILC 2641 · 35:35
    MediumGoogle · AmazonLeetCode ↗ (opens in a new tab)
  69. Reverse Odd Levels of Binary TreeLC 2415 · 35:14
    MediumGoogle · josh technologyLeetCode ↗ (opens in a new tab)
  70. Minimum Number of Operations to Sort a Binary Tree by LevelLC 2471 · 24:36
    MediumGoogle · Amazon · +1 more companiesLeetCode ↗ (opens in a new tab)
  71. Find Elements in a Contaminated Binary TreeLC 1261 · 13:03
    MediumGoogle · AmazonLeetCode ↗ (opens in a new tab)

  72. General Recursion on Trees

    0 of 33 passed
  73. Time Needed to Inform All EmployeesLC 1376 · 24:56
    MediumGoogle · Amazon · +2 more companiesLeetCode ↗ (opens in a new tab)
  74. Find Leaves Of Binary TreeLC 366 · 17:45 · LeetCode Premium
    MediumGoogle · Amazon · +4 more companiesLeetCode ↗ (opens in a new tab)
  75. Binary Tree PruningLC 814 · 16:48
    MediumGoogle · Amazon · +3 more companiesLeetCode ↗ (opens in a new tab)
  76. Binary Tree Pruning (O(n))- (Google, Amazon, Microsoft) : Explanation + Live Coding 🧑🏻‍💻👩🏻‍💻LC 814 · 6:00
    MediumGoogle · Amazon · +3 more companiesLeetCode ↗ (opens in a new tab)
  77. Count Complete Tree Nodes -(Amazon, Microsoft, Salesforce, Meta) : Explanation ➕ Live CodingLC 222 · 21:36
    MediumGoogle · Amazon · +5 more companiesLeetCode ↗ (opens in a new tab)
  78. Leaf-Similar TreesLC 872 · 8:08
    EasyGoogle · Amazon · +3 more companiesLeetCode ↗ (opens in a new tab)
  79. Maximum Product of Splitted Binary TreeLC 1339 · 29:44
    MediumGoogle · Amazon · +3 more companiesLeetCode ↗ (opens in a new tab)
  80. Same TreeLC 100 · 14:18
    EasyGoogle · Amazon · +7 more companiesLeetCode ↗ (opens in a new tab)
  81. Find Duplicate Subtrees (Leetcode - 652) - (GOOGLE) : Explanation ➕ Live CodingLC 652 · 14:11
    MediumGoogle · Amazon · +7 more companiesLeetCode ↗ (opens in a new tab)
  82. Symmetric Tree (Leetcode - 101) - (Amazon, Microsoft, Mentor (Siemens)) : Explanation ➕ Live CodingLC 101 · 10:07
    EasyGoogle · Amazon · +9 more companiesLeetCode ↗ (opens in a new tab)
  83. Sum Root to Leaf NumbersLC 129 · 12:42
    MediumGoogle · Amazon · +5 more companiesLeetCode ↗ (opens in a new tab)
  84. Maximum Width of Binary TreeLC 662 · 16:53
    MediumGoogle · Amazon · +6 more companiesLeetCode ↗ (opens in a new tab)
  85. Maximum Level Sum of a Binary TreeLC 1161 · 20:01
    MediumGoogle · Amazon · +2 more companiesLeetCode ↗ (opens in a new tab)
  86. Validate Binary Tree NodesLC 1361 · 24:42
    MediumGoogle · Meta · +1 more companiesLeetCode ↗ (opens in a new tab)
  87. Find Largest Value in Each Tree RowLC 515 · 22:53
    MediumGoogle · Amazon · +6 more companiesLeetCode ↗ (opens in a new tab)
  88. Count Nodes Equal to Average of SubtreeLC 2265 · 24:13
    MediumGoogle · Amazon · +2 more companiesLeetCode ↗ (opens in a new tab)
  89. Distribute Coins in Binary TreeLC 979 · 26:21
    MediumGoogle · Amazon · +5 more companiesLeetCode ↗ (opens in a new tab)
  90. Count the nodes at distance K from leaf45:50
    LeetCode ↗ (opens in a new tab)
  91. Find Bottom Left Tree ValueLC 513 · 23:52
    MediumGoogle · Amazon · +4 more companiesLeetCode ↗ (opens in a new tab)
  92. Smallest String Starting From LeafLC 988 · 25:37
    MediumGoogle · AmazonLeetCode ↗ (opens in a new tab)
  93. Delete Leaves With a Given ValueLC 1325 · 12:42
    MediumGoogle · Amazon · +2 more companiesLeetCode ↗ (opens in a new tab)
  94. Step-By-Step Directions From a Binary Tree Node to AnotherLC 2096 · 34:05
    MediumGoogle · Amazon · +4 more companiesLeetCode ↗ (opens in a new tab)
  95. Number of Good Leaf Nodes PairsLC 1530 · 28:55
    MediumGoogle · TikTok · +1 more companiesLeetCode ↗ (opens in a new tab)
  96. Number of Good Leaf Nodes PairsLC 1530 · 31:30
    MediumGoogle · TikTok · +1 more companiesLeetCode ↗ (opens in a new tab)
  97. Linked List in Binary TreeLC 1367 · 20:58
    MediumGoogle · Amazon · +3 more companiesLeetCode ↗ (opens in a new tab)
  98. Cousins in Binary Tree IILC 2641 · 35:35
    MediumGoogle · AmazonLeetCode ↗ (opens in a new tab)
  99. Height of Binary Tree After Subtree Removal QueriesLC 2458 · 41:20
    HardGoogle · Meta · +1 more companiesLeetCode ↗ (opens in a new tab)
  100. Reverse Odd Levels of Binary TreeLC 2415 · 35:14
    MediumGoogle · josh technologyLeetCode ↗ (opens in a new tab)
  101. Find Elements in a Contaminated Binary TreeLC 1261 · 13:03
    MediumGoogle · AmazonLeetCode ↗ (opens in a new tab)
  102. Lowest Common Ancestor of Deepest LeavesLC 1123 · 42:25
    MediumGoogle · Amazon · +2 more companiesLeetCode ↗ (opens in a new tab)
  103. Sum of Left LeavesLC 404 · 19:49
    EasyGoogle · Amazon · +4 more companiesLeetCode ↗ (opens in a new tab)
  104. Evaluate Boolean Binary TreeLC 2331 · 8:59
    EasyGoogleLeetCode ↗ (opens in a new tab)
  105. Sum of Root To Leaf Binary NumbersLC 1022 · 14:12
    EasyGoogle · Amazon · +2 more companiesLeetCode ↗ (opens in a new tab)

All 64 stations in order

  1. 1.Construct Quad Tree (Leetcode - 427) - (Google) : Explanation ➕ Live Coding (LeetCode 427)
  2. 2.Time Needed to Inform All Employees (LeetCode 1376)
  3. 3.Binary Tree Right Side View (LeetCode 199)
  4. 4.Binary Tree Right Side View (LeetCode 199)
  5. 5.Construct Binary Tree From Preorder And Inorder Traversal (LeetCode 105)
  6. 6.Lowest Common Ancestor of a Binary Tree (LeetCode 236)
  7. 7.Check Completeness of a Binary Tree (BFS) - (Meta, Amazon) : Explanation ➕ Live Coding (LeetCode 958)
  8. 8.Check Completeness of a Binary Tree (DFS) - (Meta, Amazon) : Explanation ➕ Live Coding (LeetCode 958)
  9. 9.Delete Nodes And Return Forest Solved (LeetCode 1110)
  10. 10.Find Leaves Of Binary Tree (LeetCode 366)
  11. 11.Binary Tree Pruning (LeetCode 814)
  12. 12.Binary Tree Pruning (O(n))- (Google, Amazon, Microsoft) : Explanation + Live Coding 🧑🏻‍💻👩🏻‍💻 (LeetCode 814)
  13. 13.Path Sum II (LeetCode 113)
  14. 14.Path Sum - (Amazon, Microsoft, Accolite, Adobe...) : Explanation + Live Coding 🧑🏻‍💻👩🏻‍💻 (LeetCode 112)
  15. 15.Add One Row to Tree (LeetCode 623)
  16. 16.Count Complete Tree Nodes -(Amazon, Microsoft, Salesforce, Meta) : Explanation ➕ Live Coding (LeetCode 222)
  17. 17.Leaf-Similar Trees (LeetCode 872)
  18. 18.Maximum Difference Between Node and Ancestor (LeetCode 1026)
  19. 19.Maximum Product of Splitted Binary Tree (LeetCode 1339)
  20. 20.Binary Tree Maximum Path Sum - (Google, Meta, Amazon, Flipkart) : Explanation ➕ Live Coding (LeetCode 124)
  21. 21.Binary Tree Preorder Traversal - (Microsoft, Walmart, Flipkart, Amazon) : Explanation ➕ Live Coding
  22. 22.Same Tree (LeetCode 100)
  23. 23.Find Duplicate Subtrees (Leetcode - 652) - (GOOGLE) : Explanation ➕ Live Coding (LeetCode 652)
  24. 24.Symmetric Tree (Leetcode - 101) - (Amazon, Microsoft, Mentor (Siemens)) : Explanation ➕ Live Coding (LeetCode 101)
  25. 25.Sum Root to Leaf Numbers (LeetCode 129)
  26. 26.Construct Binary Tree from Inorder and Postorder Traversal (LeetCode 106)
  27. 27.Longest ZigZag Path in a Binary Tree - (LeetCode 1372)
  28. 28.Maximum Width of Binary Tree (LeetCode 662)
  29. 29.Maximum Level Sum of a Binary Tree (LeetCode 1161)
  30. 30.Minimum Depth of Binary Tree (LeetCode 111)
  31. 31.All Nodes Distance K in Binary Tree (LeetCode 863)
  32. 32.Validate Binary Tree Nodes (LeetCode 1361)
  33. 33.Find Largest Value in Each Tree Row (LeetCode 515)
  34. 34.Count Nodes Equal to Average of Subtree (LeetCode 2265)
  35. 35.Binary Tree Inorder Traversal (LeetCode 94)
  36. 36.Amount of Time for Binary Tree to Be Infected (LeetCode 2385)
  37. 37.Amount of Time for Binary Tree to Be Infected (LeetCode 2385)
  38. 38.Distribute Coins in Binary Tree (LeetCode 979)
  39. 39.Paths from root with a specified sum
  40. 40.Pseudo-Palindromic Paths in a Binary Tree (LeetCode 1457)
  41. 41.Count the nodes at distance K from leaf
  42. 42.Diameter of Binary Tree (LeetCode 543)
  43. 43.Find Bottom Left Tree Value (LeetCode 513)
  44. 44.Even Odd Tree (LeetCode 1609)
  45. 45.Smallest String Starting From Leaf (LeetCode 988)
  46. 46.Delete Leaves With a Given Value (LeetCode 1325)
  47. 47.Create Binary Tree From Descriptions (LeetCode 2196)
  48. 48.Step-By-Step Directions From a Binary Tree Node to Another (LeetCode 2096)
  49. 49.Number of Good Leaf Nodes Pairs (LeetCode 1530)
  50. 50.Number of Good Leaf Nodes Pairs (LeetCode 1530)
  51. 51.Linked List in Binary Tree (LeetCode 1367)
  52. 52.Cousins in Binary Tree II (LeetCode 2641)
  53. 53.Flip Equivalent Binary Trees (LeetCode 951)
  54. 54.Height of Binary Tree After Subtree Removal Queries (LeetCode 2458)
  55. 55.Reverse Odd Levels of Binary Tree (LeetCode 2415)
  56. 56.Minimum Number of Operations to Sort a Binary Tree by Level (LeetCode 2471)
  57. 57.Find Elements in a Contaminated Binary Tree (LeetCode 1261)
  58. 58.Recover a Tree From Preorder Traversal (LeetCode 1028)
  59. 59.Construct Binary Tree from Preorder and Postorder Traversal (LeetCode 889)
  60. 60.Lowest Common Ancestor of Deepest Leaves (LeetCode 1123)
  61. 61.Sum of Left Leaves (LeetCode 404)
  62. 62.Evaluate Boolean Binary Tree (LeetCode 2331)
  63. 63.Balanced Binary Tree (LeetCode 110)
  64. 64.Sum of Root To Leaf Binary Numbers (LeetCode 1022)