Ordered Set Interview Questions

Linked List Stack Design Doubly-Linked List Ordered Set

Rank

#1549MediumFrequency: 94.4%

Longest Continuous Subarray With Absolute Diff Less Than or Equal to Limit

Array Queue Sliding Window Heap (Priority Queue)Ordered Set Monotonic Queue

Rank

#2023HardFrequency: 79.4%

Design Movie Rental System

Array Hash Table Design Heap (Priority Queue)Ordered Set

Rank

#729MediumFrequency: 73.4%

My Calendar I

Array Binary Search Design Segment Tree Ordered Set

Rank

#3435HardFrequency: 68.4%

Block Placement Queries

Array Binary Search Binary Indexed Tree Segment Tree Ordered Set

Rank

#220HardFrequency: 65.5%

Contains Duplicate III

Asked at Airbnb

Array Sliding Window Sorting Bucket Sort Ordered Set

Rank

#2726HardFrequency: 65.2%

Minimum Reverse Operations

Array Hash Table Breadth-First Search Union-Find Ordered Set

Rank

#3863MediumFrequency: 64.9%

Power Grid Maintenance

Array Hash Table Depth-First Search Breadth-First Search Union-Find Graph Theory Heap (Priority Queue)Ordered Set

Rank

#2466HardFrequency: 62.5%

Maximum Segment Sum After Removals

Array Union-Find Prefix Sum Ordered Set

Rank

#880HardFrequency: 59.8%

Rectangle Area II

Array Segment Tree Sweep Line Ordered Set

#10

Rank

#931HardFrequency: 57.5%

Maximum Frequency Stack

Hash Table Stack Design Ordered Set

#11

Rank

#2357HardFrequency: 56.3%

Count Integers in Intervals

#12

Rank

#885MediumFrequency: 55.1%

Exam Room

Design Heap (Priority Queue)Ordered Set

#13

Rank

#1710HardFrequency: 53.1%

Find Servers That Handled Most Number of Requests

Array Heap (Priority Queue)Simulation Ordered Set

#14

Rank

#2075MediumFrequency: 51.4%

Brightest Position on Street

Array Sorting Prefix Sum Ordered Set

#15

Rank

#456MediumFrequency: 51.3%

132 Pattern

Asked at DoorDash

Array Binary Search Stack Monotonic Stack Ordered Set

#16

Rank

#699HardFrequency: 47.5%

Falling Squares

#17

Rank

#1946MediumFrequency: 47.5%

Minimum Absolute Sum Difference

#18

Rank

#3378MediumFrequency: 47.5%

Maximum Increasing Triplet Value

Array Ordered Set

#19

Rank

#493HardFrequency: 44.6%

Reverse Pairs

Array Binary Search Divide and Conquer Binary Indexed Tree Segment Tree Merge Sort Ordered Set Treap

#20

Rank

#2334HardFrequency: 43%

Number of Flowers in Full Bloom

Asked at Databricks

Array Hash Table Binary Search Sorting Prefix Sum Ordered Set

#21

Rank

#715HardFrequency: 42.7%

Range Module

#22

Rank

#1953HardFrequency: 39.5%

Finding MK Average

Design Queue Heap (Priority Queue)Data Stream Ordered Set Treap

#23

Rank

#218HardFrequency: 37.9%

The Skyline Problem

Array Divide and Conquer Binary Indexed Tree Segment Tree Sweep Line Sorting Heap (Priority Queue)Ordered Set

#24

Rank

#1017HardFrequency: 35.8%

Odd Even Jump

Array Dynamic Programming Stack Sorting Monotonic Stack Ordered Set

#25

Rank

#635MediumFrequency: 35%

Design Log Storage System

Hash Table String Design Ordered Set

#26

Rank

#2162HardFrequency: 34.2%

Partition Array Into Two Arrays to Minimize Sum Difference

Array Two Pointers Binary Search Dynamic Programming Bit Manipulation Meet in the Middle Sorting Ordered Set Bitmask

#27

Rank

#315HardFrequency: 33.1%

Count of Smaller Numbers After Self

Array Binary Search Divide and Conquer Binary Indexed Tree Segment Tree Merge Sort Ordered Set Treap

#28

Rank

#2868MediumFrequency: 31.8%

Continuous Subarrays

Array Queue Sliding Window Heap (Priority Queue)Ordered Set Monotonic Queue

#29

Rank

#3983HardFrequency: 31.3%

Minimum Operations to Equalize Binary String

Math String Breadth-First Search Union-Find Ordered Set

#30

Rank

#327HardFrequency: 31.3%

Count of Range Sum

Array Binary Search Divide and Conquer Binary Indexed Tree Segment Tree Merge Sort Ordered Set Treap

#31

Rank

#2434MediumFrequency: 30.4%

Design a Number Container System

#32

Rank

#731MediumFrequency: 29.5%

My Calendar II

Array Binary Search Design Segment Tree Prefix Sum Ordered Set

#33

Rank

#3678MediumFrequency: 29.5%

Design Task Manager

#34

Rank

#914MediumFrequency: 27.8%

Random Point in Non-overlapping Rectangles

Array Math Binary Search Reservoir Sampling Prefix Sum Ordered Set Randomized

#35

Rank

#2413MediumFrequency: 26.5%

Smallest Number in Infinite Set

#36

Rank

#2161MediumFrequency: 25.4%

Stock Price Fluctuation

Hash Table Design Heap (Priority Queue)Data Stream Ordered Set

#37

Rank

#3710HardFrequency: 25.1%

Design an Array Statistics Tracker

Hash Table Binary Search Design Queue Heap (Priority Queue)Data Stream Ordered Set

#38

Rank

#3000MediumFrequency: 24.6%

Minimum Absolute Difference Between Elements With Constraint

Array Binary Search Ordered Set

#39

Rank

#3773EasyFrequency: 24.4%

Minimum Pair Removal to Sort Array I

Array Hash Table Linked List Heap (Priority Queue)Simulation Doubly-Linked List Ordered Set

#40

Rank

#2429MediumFrequency: 23.6%

Design a Food Rating System

Array Hash Table String Design Heap (Priority Queue)Ordered Set

#41

Rank

#3363MediumFrequency: 23.6%

Most Frequent IDs

Array Hash Table Heap (Priority Queue)Ordered Set

#42

Rank

#363HardFrequency: 22.1%

Max Sum of Rectangle No Larger Than K

Array Binary Search Matrix Prefix Sum Ordered Set

#43

Rank

#3790EasyFrequency: 22.1%

Fruits Into Baskets II

Array Binary Search Segment Tree Simulation Ordered Set

#44

Rank

#1957HardFrequency: 21.9%

Closest Room

#45

Rank

#2297HardFrequency: 20.3%

Amount of New Area Painted Each Day

#46

Rank

#2207HardFrequency: 20%

Sequentially Ordinal Rank Tracker

Design Heap (Priority Queue)Data Stream Ordered Set

#47

Rank

#2658HardFrequency: 20%

Count the Number of K-Big Indices

Array Binary Search Divide and Conquer Binary Indexed Tree Segment Tree Merge Sort Ordered Set

#48

Rank

#732HardFrequency: 19.5%

My Calendar III

Binary Search Design Segment Tree Prefix Sum Ordered Set

#49

Rank

#2512MediumFrequency: 19.5%

Longest Uploaded Prefix

Hash Table Binary Search Union-Find Design Binary Indexed Tree Segment Tree Heap (Priority Queue)Ordered Set

#50

Rank

#683HardFrequency: 18%

K Empty Slots

Array Binary Indexed Tree Segment Tree Queue Sliding Window Heap (Priority Queue)Ordered Set Monotonic Queue

#51

Rank

#2447EasyFrequency: 18%

Merge Similar Items

Array Hash Table Sorting Ordered Set

#52

Rank

#2513HardFrequency: 18%

Number of Pairs Satisfying Inequality

Array Binary Search Divide and Conquer Binary Indexed Tree Segment Tree Merge Sort Ordered Set

#53

Rank

#510MediumFrequency: 16.4%

Count Subarrays With More Ones Than Zeros

Array Hash Table Binary Search Divide and Conquer Binary Indexed Tree Segment Tree Merge Sort Ordered Set

#54

Rank

#3772HardFrequency: 15.7%

Minimum Pair Removal to Sort Array II

Array Hash Table Linked List Heap (Priority Queue)Simulation Doubly-Linked List Ordered Set

#55

Rank

#3791MediumFrequency: 14.6%

Fruits Into Baskets III

Array Binary Search Segment Tree Ordered Set

#56

Rank

#2319HardFrequency: 12%

Longest Substring of One Repeating Character

Array String Segment Tree Ordered Set

#57

Rank

#2280HardFrequency: 10.5%

Count Good Triplets in an Array

Array Binary Search Divide and Conquer Binary Indexed Tree Segment Tree Merge Sort Ordered Set

#58

Rank

#352HardFrequency: 8.1%

Data Stream as Disjoint Intervals

Hash Table Binary Search Union-Find Design Data Stream Ordered Set

#59

Rank

#1470MediumFrequency: 8.1%

Tweet Counts Per Frequency

Hash Table String Binary Search Design Sorting Ordered Set

#60

Rank

#3827MediumFrequency: 7.3%

Implement Router

Array Hash Table Binary Search Design Queue Ordered Set

#61

Rank

#4067MediumFrequency: 5.5%

Design Auction System

#62

Rank

#2765HardFrequency: 5%

Make Array Empty

Array Binary Search Greedy Binary Indexed Tree Segment Tree Sorting Ordered Set

#63

Rank

#3878HardFrequency: 5%

Maximize Count of Distinct Primes After Split

Array Hash Table Math Segment Tree Number Theory Ordered Set

#64

Rank

#1794HardFrequency: 5%

Minimize Deviation in Array

Array Greedy Heap (Priority Queue)Ordered Set

#65

Rank

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Ordered Set Interview Questions

Master 65 ordered set problems frequently asked in technical interviews. These questions test your understanding of ordered setconcepts and are essential for coding interview success.

Total Problems

Easy

Medium

Hard

Max Stack

Linked List Stack Design Doubly-Linked List Ordered Set

Rank

#1549MediumFrequency: 94.4%

Longest Continuous Subarray With Absolute Diff Less Than or Equal to Limit

Array Queue Sliding Window Heap (Priority Queue)Ordered Set Monotonic Queue

Rank

#2023HardFrequency: 79.4%

Design Movie Rental System

Array Hash Table Design Heap (Priority Queue)Ordered Set

Rank

#729MediumFrequency: 73.4%

My Calendar I

Array Binary Search Design Segment Tree Ordered Set

Rank

#3435HardFrequency: 68.4%

Block Placement Queries

Array Binary Search Binary Indexed Tree Segment Tree Ordered Set

Rank

#220HardFrequency: 65.5%

Contains Duplicate III

Asked at Airbnb

Array Sliding Window Sorting Bucket Sort Ordered Set

Rank

#2726HardFrequency: 65.2%

Minimum Reverse Operations

Array Hash Table Breadth-First Search Union-Find Ordered Set

Rank

#3863MediumFrequency: 64.9%

Power Grid Maintenance

Array Hash Table Depth-First Search Breadth-First Search Union-Find Graph Theory Heap (Priority Queue)Ordered Set

Rank

#2466HardFrequency: 62.5%

Maximum Segment Sum After Removals

Array Union-Find Prefix Sum Ordered Set

Rank

#880HardFrequency: 59.8%

Rectangle Area II

Array Segment Tree Sweep Line Ordered Set

#10

Rank

#931HardFrequency: 57.5%

Maximum Frequency Stack

Hash Table Stack Design Ordered Set

#11

Rank

#2357HardFrequency: 56.3%

Count Integers in Intervals

#12

Rank

#885MediumFrequency: 55.1%

Exam Room

Design Heap (Priority Queue)Ordered Set

#13

Rank

#1710HardFrequency: 53.1%

Find Servers That Handled Most Number of Requests

Array Heap (Priority Queue)Simulation Ordered Set

#14

Rank

#2075MediumFrequency: 51.4%

Brightest Position on Street

Array Sorting Prefix Sum Ordered Set

#15

Rank

#456MediumFrequency: 51.3%

132 Pattern

Asked at DoorDash

Array Binary Search Stack Monotonic Stack Ordered Set

#16

Rank

#699HardFrequency: 47.5%

Falling Squares

#17

Rank

#1946MediumFrequency: 47.5%

Minimum Absolute Sum Difference

#18

Rank

#3378MediumFrequency: 47.5%

Maximum Increasing Triplet Value

Array Ordered Set

#19

Rank

#493HardFrequency: 44.6%

Reverse Pairs

Array Binary Search Divide and Conquer Binary Indexed Tree Segment Tree Merge Sort Ordered Set Treap

#20

Rank

#2334HardFrequency: 43%

Number of Flowers in Full Bloom

Asked at Databricks

Array Hash Table Binary Search Sorting Prefix Sum Ordered Set

#21

Rank

#715HardFrequency: 42.7%

Range Module

#22

Rank

#1953HardFrequency: 39.5%

Finding MK Average

Design Queue Heap (Priority Queue)Data Stream Ordered Set Treap

#23

Rank

#218HardFrequency: 37.9%

The Skyline Problem

Array Divide and Conquer Binary Indexed Tree Segment Tree Sweep Line Sorting Heap (Priority Queue)Ordered Set

#24

Rank

#1017HardFrequency: 35.8%

Odd Even Jump

Array Dynamic Programming Stack Sorting Monotonic Stack Ordered Set

#25

Rank

#635MediumFrequency: 35%

Design Log Storage System

Hash Table String Design Ordered Set

#26

Rank

#2162HardFrequency: 34.2%

Partition Array Into Two Arrays to Minimize Sum Difference

Array Two Pointers Binary Search Dynamic Programming Bit Manipulation Meet in the Middle Sorting Ordered Set Bitmask

#27

Rank

#315HardFrequency: 33.1%

Count of Smaller Numbers After Self

Array Binary Search Divide and Conquer Binary Indexed Tree Segment Tree Merge Sort Ordered Set Treap

#28

Rank

#2868MediumFrequency: 31.8%

Continuous Subarrays

Array Queue Sliding Window Heap (Priority Queue)Ordered Set Monotonic Queue

#29

Rank

#3983HardFrequency: 31.3%

Minimum Operations to Equalize Binary String

Math String Breadth-First Search Union-Find Ordered Set

#30

Rank

#327HardFrequency: 31.3%

Count of Range Sum

Array Binary Search Divide and Conquer Binary Indexed Tree Segment Tree Merge Sort Ordered Set Treap

#31

Rank

#2434MediumFrequency: 30.4%

Design a Number Container System

#32

Rank

#731MediumFrequency: 29.5%

My Calendar II

Array Binary Search Design Segment Tree Prefix Sum Ordered Set

#33

Rank

#3678MediumFrequency: 29.5%

Design Task Manager

#34

Rank

#914MediumFrequency: 27.8%

Random Point in Non-overlapping Rectangles

Array Math Binary Search Reservoir Sampling Prefix Sum Ordered Set Randomized

#35

Rank

#2413MediumFrequency: 26.5%

Smallest Number in Infinite Set

#36

Rank

#2161MediumFrequency: 25.4%

Stock Price Fluctuation

Hash Table Design Heap (Priority Queue)Data Stream Ordered Set

#37

Rank

#3710HardFrequency: 25.1%

Design an Array Statistics Tracker

Hash Table Binary Search Design Queue Heap (Priority Queue)Data Stream Ordered Set

#38

Rank

#3000MediumFrequency: 24.6%

Minimum Absolute Difference Between Elements With Constraint

Array Binary Search Ordered Set

#39

Rank

#3773EasyFrequency: 24.4%

Minimum Pair Removal to Sort Array I

Array Hash Table Linked List Heap (Priority Queue)Simulation Doubly-Linked List Ordered Set

#40

Rank

#2429MediumFrequency: 23.6%

Design a Food Rating System

Array Hash Table String Design Heap (Priority Queue)Ordered Set

#41

Rank

#3363MediumFrequency: 23.6%

Most Frequent IDs

Array Hash Table Heap (Priority Queue)Ordered Set

#42

Rank

#363HardFrequency: 22.1%

Max Sum of Rectangle No Larger Than K

Array Binary Search Matrix Prefix Sum Ordered Set

#43

Rank

#3790EasyFrequency: 22.1%

Fruits Into Baskets II

Array Binary Search Segment Tree Simulation Ordered Set

#44

Rank

#1957HardFrequency: 21.9%

Closest Room

#45

Rank

#2297HardFrequency: 20.3%

Amount of New Area Painted Each Day

#46

Rank

#2207HardFrequency: 20%

Sequentially Ordinal Rank Tracker

Design Heap (Priority Queue)Data Stream Ordered Set

#47

Rank

#2658HardFrequency: 20%

Count the Number of K-Big Indices

Array Binary Search Divide and Conquer Binary Indexed Tree Segment Tree Merge Sort Ordered Set

#48

Rank

#732HardFrequency: 19.5%

My Calendar III

Binary Search Design Segment Tree Prefix Sum Ordered Set

#49

Rank

#2512MediumFrequency: 19.5%

Longest Uploaded Prefix

Hash Table Binary Search Union-Find Design Binary Indexed Tree Segment Tree Heap (Priority Queue)Ordered Set

#50

Rank

#683HardFrequency: 18%

K Empty Slots

Array Binary Indexed Tree Segment Tree Queue Sliding Window Heap (Priority Queue)Ordered Set Monotonic Queue

#51

Rank

#2447EasyFrequency: 18%

Merge Similar Items

Array Hash Table Sorting Ordered Set

#52

Rank

#2513HardFrequency: 18%

Number of Pairs Satisfying Inequality

Array Binary Search Divide and Conquer Binary Indexed Tree Segment Tree Merge Sort Ordered Set

#53

Rank

#510MediumFrequency: 16.4%

Count Subarrays With More Ones Than Zeros

Array Hash Table Binary Search Divide and Conquer Binary Indexed Tree Segment Tree Merge Sort Ordered Set

#54

Rank

#3772HardFrequency: 15.7%

Minimum Pair Removal to Sort Array II

Array Hash Table Linked List Heap (Priority Queue)Simulation Doubly-Linked List Ordered Set

#55

Rank

#3791MediumFrequency: 14.6%

Fruits Into Baskets III

Array Binary Search Segment Tree Ordered Set

#56

Rank

#2319HardFrequency: 12%

Longest Substring of One Repeating Character

Array String Segment Tree Ordered Set

#57

Rank

#2280HardFrequency: 10.5%

Count Good Triplets in an Array

Array Binary Search Divide and Conquer Binary Indexed Tree Segment Tree Merge Sort Ordered Set

#58

Rank

#352HardFrequency: 8.1%

Data Stream as Disjoint Intervals

Hash Table Binary Search Union-Find Design Data Stream Ordered Set

#59

Rank

#1470MediumFrequency: 8.1%

Tweet Counts Per Frequency

Hash Table String Binary Search Design Sorting Ordered Set

#60

Rank

#3827MediumFrequency: 7.3%

Implement Router

Array Hash Table Binary Search Design Queue Ordered Set

#61

Rank

#4067MediumFrequency: 5.5%

Design Auction System

#62

Rank

#2765HardFrequency: 5%

Make Array Empty

Array Binary Search Greedy Binary Indexed Tree Segment Tree Sorting Ordered Set

#63

Rank

#3878HardFrequency: 5%

Maximize Count of Distinct Primes After Split

Array Hash Table Math Segment Tree Number Theory Ordered Set

#64

Rank

#1794HardFrequency: 5%

Minimize Deviation in Array