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The House of Online Judge Series' Articles

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Top Competitors | HackerRank | MSSQL
Cover image for Top Competitors | HackerRank | MSSQL

Top Competitors | HackerRank | MSSQL

8
Comments
2 min read
Reverse String | LeetCode | Python
Cover image for Reverse String | LeetCode | Python

Reverse String | LeetCode | Python

3
Comments
1 min read
Merge the Tools! | HackerRank | Python
Cover image for Merge the Tools! | HackerRank | Python

Merge the Tools! | HackerRank | Python

2
Comments
3 min read
Combine Two Tables | LeetCode | MSSQL
Cover image for Combine Two Tables | LeetCode | MSSQL

Combine Two Tables | LeetCode | MSSQL

Comments
2 min read
collections.Counter() | HackerRank | Python
Cover image for collections.Counter() | HackerRank | Python

collections.Counter() | HackerRank | Python

1
Comments
2 min read
Ollivander's Inventory | HackerRank | MSSQL
Cover image for Ollivander's Inventory | HackerRank | MSSQL

Ollivander's Inventory | HackerRank | MSSQL

7
Comments
3 min read
Day 15: Linked List | HackerRank | Python
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Day 15: Linked List | HackerRank | Python

1
Comments
4 min read
Customer Placing the Largest Number of Orders | LeetCode | MSSQL
Cover image for Customer Placing the Largest Number of Orders | LeetCode | MSSQL

Customer Placing the Largest Number of Orders | LeetCode | MSSQL

5
Comments
2 min read
Triangle Judgement | LeetCode | MSSQL
Cover image for Triangle Judgement | LeetCode | MSSQL

Triangle Judgement | LeetCode | MSSQL

1
Comments
2 min read
Sales Person | LeetCode | MSSQL
Cover image for Sales Person | LeetCode | MSSQL

Sales Person | LeetCode | MSSQL

2
Comments 2
3 min read
Day 16: Exceptions - String to Integer | HackerRank | Python
Cover image for Day 16: Exceptions - String to Integer | HackerRank | Python

Day 16: Exceptions - String to Integer | HackerRank | Python

2
Comments
3 min read
Employees Earning More Than Their Managers | LeetCode | MSSQL
Cover image for Employees Earning More Than Their Managers | LeetCode | MSSQL

Employees Earning More Than Their Managers | LeetCode | MSSQL

2
Comments
2 min read
Department Top Three Salaries | LeetCode | MSSQL
Cover image for Department Top Three Salaries | LeetCode | MSSQL

Department Top Three Salaries | LeetCode | MSSQL

2
Comments
2 min read
Challenges | HackerRank | MSSQL
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Challenges | HackerRank | MSSQL

10
Comments
4 min read
Trips and Users | LeetCode | MSSQL
Cover image for Trips and Users | LeetCode | MSSQL

Trips and Users | LeetCode | MSSQL

1
Comments
5 min read
Contest Leaderboard | HackerRank | MSSQL
Cover image for Contest Leaderboard | HackerRank | MSSQL

Contest Leaderboard | HackerRank | MSSQL

2
Comments
4 min read
Duplicate Emails | LeetCode | MSSQL
Cover image for Duplicate Emails | LeetCode | MSSQL

Duplicate Emails | LeetCode | MSSQL

Comments
2 min read
Customers Who Never Order | LeetCode | MSSQL
Cover image for Customers Who Never Order | LeetCode | MSSQL

Customers Who Never Order | LeetCode | MSSQL

Comments
3 min read
Delete Duplicate Emails | LeetCode | MSSQL
Cover image for Delete Duplicate Emails | LeetCode | MSSQL

Delete Duplicate Emails | LeetCode | MSSQL

3
Comments 1
2 min read
Rising Temperature | LeetCode | MSSQL
Cover image for Rising Temperature | LeetCode | MSSQL

Rising Temperature | LeetCode | MSSQL

2
Comments
2 min read
Employee Bonus | LeetCode | MSSQL
Cover image for Employee Bonus | LeetCode | MSSQL

Employee Bonus | LeetCode | MSSQL

4
Comments 1
2 min read
Find Customer Referee | LeetCode | MSSQL
Cover image for Find Customer Referee | LeetCode | MSSQL

Find Customer Referee | LeetCode | MSSQL

Comments
2 min read
Big Countries | LeetCode | MSSQL
Cover image for Big Countries | LeetCode | MSSQL

Big Countries | LeetCode | MSSQL

1
Comments 3
2 min read
Classes More Than 5 Students | LeetCode | MSSQL
Cover image for Classes More Than 5 Students | LeetCode | MSSQL

Classes More Than 5 Students | LeetCode | MSSQL

1
Comments 1
2 min read
Biggest Single Number | LeetCode | MSSQL
Cover image for Biggest Single Number | LeetCode | MSSQL

Biggest Single Number | LeetCode | MSSQL

5
Comments
2 min read
Not Boring Movies | LeetCode | MSSQL
Cover image for Not Boring Movies | LeetCode | MSSQL

Not Boring Movies | LeetCode | MSSQL

1
Comments
2 min read
Swap Salary | LeetCode | MSSQL
Cover image for Swap Salary | LeetCode | MSSQL

Swap Salary | LeetCode | MSSQL

Comments
3 min read
Actors and Directors Who Cooperated At Least Three Times | LeetCode | MSSQL
Cover image for Actors and Directors Who Cooperated At Least Three Times | LeetCode | MSSQL

Actors and Directors Who Cooperated At Least Three Times | LeetCode | MSSQL

1
Comments
3 min read
Product Sales Analysis I | LeetCode | MSSQL
Cover image for Product Sales Analysis I | LeetCode | MSSQL

Product Sales Analysis I | LeetCode | MSSQL

4
Comments
4 min read
Project Employees I | LeetCode | MSSQL
Cover image for Project Employees I | LeetCode | MSSQL

Project Employees I | LeetCode | MSSQL

1
Comments
2 min read
Article Views I | LeetCode | MSSQL
Cover image for Article Views I | LeetCode | MSSQL

Article Views I | LeetCode | MSSQL

1
Comments
2 min read
Reformat Department Table | LeetCode | MSSQL
Cover image for Reformat Department Table | LeetCode | MSSQL

Reformat Department Table | LeetCode | MSSQL

Comments
4 min read
Human Traffic of Stadium | LeetCode | MSSQL
Cover image for Human Traffic of Stadium | LeetCode | MSSQL

Human Traffic of Stadium | LeetCode | MSSQL

Comments
4 min read
Second Highest Salary | LeetCode | MSSQL
Cover image for Second Highest Salary | LeetCode | MSSQL

Second Highest Salary | LeetCode | MSSQL

4
Comments
2 min read
Nth Highest Salary | LeetCode | MSSQL
Cover image for Nth Highest Salary | LeetCode | MSSQL

Nth Highest Salary | LeetCode | MSSQL

Comments 2
2 min read
Rank Scores | LeetCode | MSSQL
Cover image for Rank Scores | LeetCode | MSSQL

Rank Scores | LeetCode | MSSQL

1
Comments
2 min read
Consecutive Numbers | LeetCode | MSSQL
Cover image for Consecutive Numbers | LeetCode | MSSQL

Consecutive Numbers | LeetCode | MSSQL

43
Comments 1
4 min read
Department Highest Salary | LeetCode | MSSQL
Cover image for Department Highest Salary | LeetCode | MSSQL

Department Highest Salary | LeetCode | MSSQL

Comments
4 min read
Game Play Analysis IV | LeetCode | MSSQL
Cover image for Game Play Analysis IV | LeetCode | MSSQL

Game Play Analysis IV | LeetCode | MSSQL

7
Comments
4 min read
Managers with at Least 5 Direct Reports | LeetCode | MSSQL
Cover image for Managers with at Least 5 Direct Reports | LeetCode | MSSQL

Managers with at Least 5 Direct Reports | LeetCode | MSSQL

14
Comments 1
3 min read
Queries Quality and Percentage | LeetCode | MSSQL
Cover image for Queries Quality and Percentage | LeetCode | MSSQL

Queries Quality and Percentage | LeetCode | MSSQL

Comments
3 min read
Average Selling Price | LeetCode | MSSQL
Cover image for Average Selling Price | LeetCode | MSSQL

Average Selling Price | LeetCode | MSSQL

11
Comments 1
3 min read
Students and Examinations | LeetCode | MSSQL
Cover image for Students and Examinations | LeetCode | MSSQL

Students and Examinations | LeetCode | MSSQL

9
Comments
4 min read
List the Products Ordered in a Period | LeetCode | MSSQL
Cover image for List the Products Ordered in a Period | LeetCode | MSSQL

List the Products Ordered in a Period | LeetCode | MSSQL

1
Comments
3 min read
Replace Employee ID With The Unique Identifier | LeetCode | MSSQL
Cover image for Replace Employee ID With The Unique Identifier | LeetCode | MSSQL

Replace Employee ID With The Unique Identifier | LeetCode | MSSQL

3
Comments
3 min read
Top Travellers | LeetCode | MSSQL
Cover image for Top Travellers | LeetCode | MSSQL

Top Travellers | LeetCode | MSSQL

2
Comments
3 min read
SQL Project Planning | HackerRank | MSSQL
Cover image for SQL Project Planning | HackerRank | MSSQL

SQL Project Planning | HackerRank | MSSQL

5
Comments
2 min read
Group Sold Products By The Date | LeetCode | MSSQL
Cover image for Group Sold Products By The Date | LeetCode | MSSQL

Group Sold Products By The Date | LeetCode | MSSQL

1
Comments
2 min read
Find Users With Valid E-Mails | LeetCode | MSSQL
Cover image for Find Users With Valid E-Mails | LeetCode | MSSQL

Find Users With Valid E-Mails | LeetCode | MSSQL

5
Comments
4 min read
Patients With a Condition | LeetCode | MSSQL
Cover image for Patients With a Condition | LeetCode | MSSQL

Patients With a Condition | LeetCode | MSSQL

Comments
3 min read
Customer Who Visited but Did Not Make Any Transactions | LeetCode | MSSQL
Cover image for Customer Who Visited but Did Not Make Any Transactions | LeetCode | MSSQL

Customer Who Visited but Did Not Make Any Transactions | LeetCode | MSSQL

6
Comments
5 min read
Bank Account Summary II | LeetCode | MSSQL
Cover image for Bank Account Summary II | LeetCode | MSSQL

Bank Account Summary II | LeetCode | MSSQL

1
Comments
3 min read
Percentage of Users Attended a Contest | LeetCode | MSSQL
Cover image for Percentage of Users Attended a Contest | LeetCode | MSSQL

Percentage of Users Attended a Contest | LeetCode | MSSQL

Comments
3 min read
Average Time of Process per Machine | LeetCode | MSSQL
Cover image for Average Time of Process per Machine | LeetCode | MSSQL

Average Time of Process per Machine | LeetCode | MSSQL

8
Comments
4 min read
Fix Names in a Table | LeetCode | MSSQL
Cover image for Fix Names in a Table | LeetCode | MSSQL

Fix Names in a Table | LeetCode | MSSQL

2
Comments
2 min read
Invalid Tweets | LeetCode | MSSQL
Cover image for Invalid Tweets | LeetCode | MSSQL

Invalid Tweets | LeetCode | MSSQL

1
Comments
2 min read
Placements | HackerRank | MSSQL
Cover image for Placements | HackerRank | MSSQL

Placements | HackerRank | MSSQL

4
Comments
3 min read
Symmetric Pairs | HackerRank | MSSQL
Cover image for Symmetric Pairs | HackerRank | MSSQL

Symmetric Pairs | HackerRank | MSSQL

12
Comments 1
3 min read
Daily Leads and Partners | LeetCode | MSSQL
Cover image for Daily Leads and Partners | LeetCode | MSSQL

Daily Leads and Partners | LeetCode | MSSQL

1
Comments 1
3 min read
Find Followers Count | LeetCode | MSSQL
Cover image for Find Followers Count | LeetCode | MSSQL

Find Followers Count | LeetCode | MSSQL

1
Comments
2 min read
The Number of Employees Which Report to Each Employee | LeetCode | MSSQL
Cover image for The Number of Employees Which Report to Each Employee | LeetCode | MSSQL

The Number of Employees Which Report to Each Employee | LeetCode | MSSQL

Comments 1
4 min read
Find Total Time Spent by Each Employee | LeetCode | MSSQL
Cover image for Find Total Time Spent by Each Employee | LeetCode | MSSQL

Find Total Time Spent by Each Employee | LeetCode | MSSQL

2
Comments
2 min read
Recyclable and Low Fat Products | LeetCode | MSSQL
Cover image for Recyclable and Low Fat Products | LeetCode | MSSQL

Recyclable and Low Fat Products | LeetCode | MSSQL

1
Comments
2 min read