Depth First Search Interview Questions

Array String Depth-First Search Breadth-First Search Graph

Rank

#314MediumFrequency: 97%

Binary Tree Vertical Order Traversal

Hash Table Tree Depth-First Search Breadth-First Search Sorting Binary Tree

Rank

#364MediumFrequency: 88%

Nested List Weight Sum II

Stack Depth-First Search Breadth-First Search

Rank

#200MediumFrequency: 88%

Number of Islands

Asked at Salesforce

Array Depth-First Search Breadth-First Search Union Find Matrix

Rank

#339MediumFrequency: 84%

Nested List Weight Sum

Depth-First Search Breadth-First Search

Rank

#366MediumFrequency: 84%

Find Leaves of Binary Tree

Rank

#124HardFrequency: 83%

Binary Tree Maximum Path Sum

Dynamic Programming Tree Depth-First Search Binary Tree

Rank

#236MediumFrequency: 79%

Lowest Common Ancestor of a Binary Tree

Rank

#269HardFrequency: 79%

Alien Dictionary

Array String Depth-First Search Breadth-First Search Graph Topological Sort

Rank

#199MediumFrequency: 76%

Binary Tree Right Side View

Tree Depth-First Search Breadth-First Search Binary Tree

#10

Rank

#543EasyFrequency: 74%

Diameter of Binary Tree

#11

Rank

#975EasyFrequency: 73%

Range Sum of BST

Tree Depth-First Search Binary Search Tree Binary Tree

#12

Rank

#329HardFrequency: 73%

Longest Increasing Path in a Matrix

Array Dynamic Programming Depth-First Search Breadth-First Search Graph Topological Sort Memoization Matrix

#13

Rank

#235MediumFrequency: 72%

Lowest Common Ancestor of a Binary Search Tree

Tree Depth-First Search Binary Search Tree Binary Tree

#14

Rank

#129MediumFrequency: 68%

Sum Root to Leaf Numbers

Array Depth-First Search Breadth-First Search Matrix

#15

Rank

#733EasyFrequency: 66%

Flood Fill

Asked at Microsoft

#16

Rank

#758MediumFrequency: 64%

Convert Binary Search Tree to Sorted Doubly Linked List

Linked List Stack Tree Depth-First Search Binary Search Tree Binary Tree Doubly-Linked List

#17

Rank

#893MediumFrequency: 64%

All Nodes Distance K in Binary Tree

Hash Table Tree Depth-First Search Breadth-First Search Binary Tree

#18

Rank

#399MediumFrequency: 63%

Evaluate Division

Array String Depth-First Search Breadth-First Search Union Find Graph Shortest Path

#19

Rank

#270EasyFrequency: 62%

Closest Binary Search Tree Value

Binary Search Tree Depth-First Search Binary Search Tree Binary Tree

#20

Rank

#721MediumFrequency: 62%

Accounts Merge

Array Hash Table String Depth-First Search Breadth-First Search Union Find Sorting

#21

Rank

#694MediumFrequency: 62%

Number of Distinct Islands

Asked at TikTok

Hash Table Depth-First Search Breadth-First Search Union Find Hash Function

#22

Rank

#133MediumFrequency: 60%

Clone Graph

Hash Table Depth-First Search Breadth-First Search Graph

#23

Rank

#854HardFrequency: 60%

Making A Large Island

Array Depth-First Search Breadth-First Search Union Find Matrix

#24

Rank

#1029HardFrequency: 60%

Vertical Order Traversal of a Binary Tree

Hash Table Tree Depth-First Search Breadth-First Search Sorting Binary Tree

#25

Rank

#207MediumFrequency: 56%

Course Schedule

Depth-First Search Breadth-First Search Graph Topological Sort

#26

Rank

#114MediumFrequency: 53%

Flatten Binary Tree to Linked List

Linked List Stack Tree Depth-First Search Binary Tree

#27

Rank

#116MediumFrequency: 51%

Populating Next Right Pointers in Each Node

Linked List Tree Depth-First Search Breadth-First Search Binary Tree

#28

Rank

#545MediumFrequency: 47%

Boundary of Binary Tree

#29

Rank

#100EasyFrequency: 43%

Same Tree

Tree Depth-First Search Breadth-First Search Binary Tree

#30

Rank

#230MediumFrequency: 37%

Kth Smallest Element in a BST

Tree Depth-First Search Binary Search Tree Binary Tree

#31

Rank

#104EasyFrequency: 36%

Maximum Depth of Binary Tree

Asked at Amazon

Tree Depth-First Search Breadth-First Search Binary Tree

#32

Rank

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Depth First Search Interview Questions

Master 32 depth first search problems frequently asked in technical interviews. These questions test your understanding of depth first searchconcepts and are essential for coding interview success.

Total Problems

Easy

Medium

Hard

Maximize Amount After Two Days of Conversions

Array String Depth-First Search Breadth-First Search Graph

Rank

#314MediumFrequency: 97%

Binary Tree Vertical Order Traversal

Hash Table Tree Depth-First Search Breadth-First Search Sorting Binary Tree

Rank

#364MediumFrequency: 88%

Nested List Weight Sum II

Stack Depth-First Search Breadth-First Search

Rank

#200MediumFrequency: 88%

Number of Islands

Asked at Salesforce

Array Depth-First Search Breadth-First Search Union Find Matrix

Rank

#339MediumFrequency: 84%

Nested List Weight Sum

Depth-First Search Breadth-First Search

Rank

#366MediumFrequency: 84%

Find Leaves of Binary Tree

Rank

#124HardFrequency: 83%

Binary Tree Maximum Path Sum

Dynamic Programming Tree Depth-First Search Binary Tree

Rank

#236MediumFrequency: 79%

Lowest Common Ancestor of a Binary Tree

Rank

#269HardFrequency: 79%

Alien Dictionary

Array String Depth-First Search Breadth-First Search Graph Topological Sort

Rank

#199MediumFrequency: 76%

Binary Tree Right Side View

Tree Depth-First Search Breadth-First Search Binary Tree

#10

Rank

#543EasyFrequency: 74%

Diameter of Binary Tree

#11

Rank

#975EasyFrequency: 73%

Range Sum of BST

Tree Depth-First Search Binary Search Tree Binary Tree

#12

Rank

#329HardFrequency: 73%

Longest Increasing Path in a Matrix

Array Dynamic Programming Depth-First Search Breadth-First Search Graph Topological Sort Memoization Matrix

#13

Rank

#235MediumFrequency: 72%

Lowest Common Ancestor of a Binary Search Tree

Tree Depth-First Search Binary Search Tree Binary Tree

#14

Rank

#129MediumFrequency: 68%

Sum Root to Leaf Numbers

Array Depth-First Search Breadth-First Search Matrix

#15

Rank

#733EasyFrequency: 66%

Flood Fill

Asked at Microsoft

#16

Rank

#758MediumFrequency: 64%

Convert Binary Search Tree to Sorted Doubly Linked List

Linked List Stack Tree Depth-First Search Binary Search Tree Binary Tree Doubly-Linked List

#17

Rank

#893MediumFrequency: 64%

All Nodes Distance K in Binary Tree

Hash Table Tree Depth-First Search Breadth-First Search Binary Tree

#18

Rank

#399MediumFrequency: 63%

Evaluate Division

Array String Depth-First Search Breadth-First Search Union Find Graph Shortest Path

#19

Rank

#270EasyFrequency: 62%

Closest Binary Search Tree Value

Binary Search Tree Depth-First Search Binary Search Tree Binary Tree

#20

Rank

#721MediumFrequency: 62%

Accounts Merge

Array Hash Table String Depth-First Search Breadth-First Search Union Find Sorting

#21

Rank

#694MediumFrequency: 62%

Number of Distinct Islands

Asked at TikTok

Hash Table Depth-First Search Breadth-First Search Union Find Hash Function

#22

Rank

#133MediumFrequency: 60%

Clone Graph

Hash Table Depth-First Search Breadth-First Search Graph

#23

Rank

#854HardFrequency: 60%

Making A Large Island

Array Depth-First Search Breadth-First Search Union Find Matrix

#24

Rank

#1029HardFrequency: 60%

Vertical Order Traversal of a Binary Tree

Hash Table Tree Depth-First Search Breadth-First Search Sorting Binary Tree

#25

Rank

#207MediumFrequency: 56%

Course Schedule

Depth-First Search Breadth-First Search Graph Topological Sort

#26

Rank

#114MediumFrequency: 53%

Flatten Binary Tree to Linked List

Linked List Stack Tree Depth-First Search Binary Tree

#27

Rank

#116MediumFrequency: 51%

Populating Next Right Pointers in Each Node

Linked List Tree Depth-First Search Breadth-First Search Binary Tree

#28

Rank

#545MediumFrequency: 47%

Boundary of Binary Tree

#29

Rank

#100EasyFrequency: 43%

Same Tree

Tree Depth-First Search Breadth-First Search Binary Tree

#30

Rank

#230MediumFrequency: 37%

Kth Smallest Element in a BST