Solutions & Explanations

Browse 4,029+ detailed solutions with multiple approaches, code in Python, Java, C++ and more.

4,029 Solutions961 Easy2102 Medium966 Hard

Title	Difficulty	Acceptance	Topics	Solution
1056. Confusing Number	Easy	49.8%	Math	Read
1064. Fixed Point	Easy	64.1%	Array Binary Search	Read
1065. Index Pairs of a String	Easy	68.6%	Array Sorting+2	Read
1068. Product Sales Analysis I	Easy	85.3%	Database	Read
1069. Product Sales Analysis II	Easy	82.1%	Database	Read
1071. Greatest Common Divisor of Strings	Easy	54.1%	Math String	Read
1075. Project Employees I	Easy	64.2%	Database	Read
1076. Project Employees II	Easy	50.1%	Database	Read
1078. Occurrences After Bigram	Easy	64.1%	String	Read
1082. Sales Analysis I	Easy	74.6%	Database	Read
1083. Sales Analysis II	Easy	49.8%	Database	Read
1084. Sales Analysis III	Easy	46.8%	Database	Read
1085. Sum of Digits in the Minimum Number	Easy	76.6%	Array Math	Read
1086. High Five	Easy	74.5%	Array Hash Table+2	Read
1089. Duplicate Zeros	Easy	54.1%	Array Two Pointers	Read
1099. Two Sum Less Than K	Easy	61.9%	Array Binary Search+2	Read
1103. Distribute Candies to People	Easy	67.5%	Math Simulation	Read
1108. Defanging an IP Address	Easy	90.0%	String	Read
1113. Reported Posts	Easy	65.0%	Database	Read
1114. Print in Order	Easy	70.3%	Concurrency	Read
1118. Number of Days in a Month	Easy	59.4%	Math	Read
1119. Remove Vowels from a String	Easy	91.2%	String	Read
1122. Relative Sort Array	Easy	75.4%	Array Counting Sort+2	Read
1128. Number of Equivalent Domino Pairs	Easy	60.7%	Array Counting+1	Read
1133. Largest Unique Number	Easy	71.3%	Array Hash Table+1	Read
1134. Armstrong Number	Easy	77.8%	Math	Read
1137. N-th Tribonacci Number	Easy	63.2%	Dynamic Programming Math+1	Read
1141. User Activity for the Past 30 Days I	Easy	49.2%	Database	Read
1142. User Activity for the Past 30 Days II	Easy	35.7%	Database	Read
1148. Article Views I	Easy	76.8%	Database	Read
1150. Check If a Number Is Majority Element in a Sorted Array	Easy	59.9%	Array Binary Search	Read
1154. Day of the Year	Easy	50.3%	Math String	Read
1160. Find Words That Can Be Formed by Characters	Easy	71.5%	Array Counting+2	Read
1165. Single-Row Keyboard	Easy	87.6%	Hash Table String	Read
1173. Immediate Food Delivery I	Easy	80.9%	Database	Read
1175. Prime Arrangements	Easy	63.3%	Math	Read
1176. Diet Plan Performance	Easy	55.9%	Array Sliding Window	Read
1179. Reformat Department Table	Easy	76.9%	Database	Read
1180. Count Substrings with Only One Distinct Letter	Easy	80.9%	Math String	Read
1184. Distance Between Bus Stops	Easy	56.7%	Array	Read
1185. Day of the Week	Easy	59.6%	Math	Read
1189. Maximum Number of Balloons	Easy	64.1%	Counting Hash Table+1	Read
1196. How Many Apples Can You Put into the Basket	Easy	67.0%	Array Greedy+1	Read
1200. Minimum Absolute Difference	Easy	75.1%	Array Sorting	Read
1207. Unique Number of Occurrences	Easy	78.7%	Array Hash Table	Read
1211. Queries Quality and Percentage	Easy	43.6%	Database	Read
1213. Intersection of Three Sorted Arrays	Easy	80.2%	Array Binary Search+2	Read
1217. Minimum Cost to Move Chips to The Same Position	Easy	72.8%	Array Greedy+1	Read
1221. Split a String in Balanced Strings	Easy	87.3%	Counting Greedy+1	Read
1228. Missing Number In Arithmetic Progression	Easy	52.0%	Array Math	Read

#1056Easy

Confusing Number

Math

Acceptance: 49.8%

#1064Easy

Fixed Point

ArrayBinary Search

Acceptance: 64.1%

#1065Easy

Index Pairs of a String

ArraySortingString+1

Acceptance: 68.6%

#1068Easy

Product Sales Analysis I

Database

Acceptance: 85.3%

#1069Easy

Product Sales Analysis II

Database

Acceptance: 82.1%

#1071Easy

Greatest Common Divisor of Strings

MathString

Acceptance: 54.1%

#1075Easy

Project Employees I

Database

Acceptance: 64.2%

#1076Easy

Project Employees II

Database

Acceptance: 50.1%

#1078Easy

Occurrences After Bigram

String

Acceptance: 64.1%

#1082Easy

Sales Analysis I

Database

Acceptance: 74.6%

#1083Easy

Sales Analysis II

Database

Acceptance: 49.8%

#1084Easy

Sales Analysis III

Database

Acceptance: 46.8%

#1085Easy

Sum of Digits in the Minimum Number

ArrayMath

Acceptance: 76.6%

#1086Easy

High Five

ArrayHash TableHeap (Priority Queue)+1

Acceptance: 74.5%

#1089Easy

Duplicate Zeros

ArrayTwo Pointers

Acceptance: 54.1%

#1099Easy

Two Sum Less Than K

ArrayBinary SearchSorting+1

Acceptance: 61.9%

#1103Easy

Distribute Candies to People

MathSimulation

Acceptance: 67.5%

#1108Easy

Defanging an IP Address

String

Acceptance: 90.0%

#1113Easy

Reported Posts

Database

Acceptance: 65.0%

#1114Easy

Print in Order

Concurrency

Acceptance: 70.3%

#1118Easy

Number of Days in a Month

Math

Acceptance: 59.4%

#1119Easy

Remove Vowels from a String

String

Acceptance: 91.2%

#1122Easy

Relative Sort Array

ArrayCounting SortHash Table+1

Acceptance: 75.4%

#1128Easy

Number of Equivalent Domino Pairs

ArrayCountingHash Table

Acceptance: 60.7%

#1133Easy

Largest Unique Number

ArrayHash TableSorting

Acceptance: 71.3%

#1134Easy

Armstrong Number

Math

Acceptance: 77.8%

#1137Easy

N-th Tribonacci Number

Dynamic ProgrammingMathMemoization

Acceptance: 63.2%

#1141Easy

User Activity for the Past 30 Days I

Database

Acceptance: 49.2%

#1142Easy

User Activity for the Past 30 Days II

Database

Acceptance: 35.7%

#1148Easy

Article Views I

Database

Acceptance: 76.8%

#1150Easy

Check If a Number Is Majority Element in a Sorted Array

ArrayBinary Search

Acceptance: 59.9%

#1154Easy

Day of the Year

MathString

Acceptance: 50.3%

#1160Easy

Find Words That Can Be Formed by Characters

ArrayCountingHash Table+1

Acceptance: 71.5%

#1165Easy

Single-Row Keyboard

Hash TableString

Acceptance: 87.6%

#1173Easy

Immediate Food Delivery I

Database

Acceptance: 80.9%

#1175Easy

Prime Arrangements

Math

Acceptance: 63.3%

#1176Easy

Diet Plan Performance

ArraySliding Window

Acceptance: 55.9%

#1179Easy

Reformat Department Table

Database

Acceptance: 76.9%

#1180Easy

Count Substrings with Only One Distinct Letter

MathString

Acceptance: 80.9%

#1184Easy

Distance Between Bus Stops

Array

Acceptance: 56.7%

#1185Easy

Day of the Week

Math

Acceptance: 59.6%

#1189Easy

Maximum Number of Balloons

CountingHash TableString

Acceptance: 64.1%

#1196Easy

How Many Apples Can You Put into the Basket

ArrayGreedySorting

Acceptance: 67.0%

#1200Easy

Minimum Absolute Difference

ArraySorting

Acceptance: 75.1%

#1207Easy

Unique Number of Occurrences

ArrayHash Table

Acceptance: 78.7%

#1211Easy

Queries Quality and Percentage

Database

Acceptance: 43.6%

#1213Easy

Intersection of Three Sorted Arrays

ArrayBinary SearchCounting+1

Acceptance: 80.2%

#1217Easy

Minimum Cost to Move Chips to The Same Position

ArrayGreedyMath

Acceptance: 72.8%

#1221Easy

Split a String in Balanced Strings

CountingGreedyString

Acceptance: 87.3%

#1228Easy

Missing Number In Arithmetic Progression

ArrayMath

Acceptance: 52.0%

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Master DSA with Step-by-Step Solutions

Each solution article on FleetCode breaks down the problem into multiple approaches, from brute force to optimal, with detailed explanations and code in Python, Java, C++ and more. Understanding why an approach works - not just copying code - is what separates candidates who clear interviews from those who don't.

How to Use These Solutions

Try the problem first: Spend at least 20 minutes before reading the solution
Read all approaches: Start from brute force to understand the problem fully, then study the optimized solution
Understand the complexity: Pay attention to time and space analysis for each approach
Code it yourself: After understanding the approach, close the solution and implement from memory
Revisit after a week: Spaced repetition helps retain problem-solving patterns