HackerRank

Welcome to my repository of solutions for HackerRank problems!
Here, you will find my solutions to various coding challenges on SQL, Python, Linux Shell, and Database.
These solutions have been tested and verified to work correctly on the HackerRank platform.

1. SQL Problems:

ID	Problem	DIFFICULTY
01	Revising the Select Query I	Easy
02	Revising the Select Query II	Easy
03	Select All	Easy
04	Select By ID	Easy
05	Japanese Cities' Attributes	Easy
06	Japanese Cities' Names	Easy
07	Weather Observation Station 1	Easy
08	Weather Observation Station 3	Easy
09	Weather Observation Station 4	Easy
10	Weather Observation Station 5	Easy
11	Weather Observation Station 6	Easy
12	Weather Observation Station 7	Easy
13	Weather Observation Station 8	Easy
14	Weather Observation Station 9	Easy
15	Weather Observation Station 10	Easy
16	Weather Observation Station 11	Easy
17	Weather Observation Station 12	Easy
18	Higher Than 75 Marks	Easy
19	Employee Names	Easy
20	Employee Salaries	Easy
21	Type of Triangle	Easy
22	Revising Aggregations - The Count Function	Easy
23	Revising Aggregations - The Sum Function	Easy
24	Revising Aggregations - Averages	Easy
25	Average Population	Easy
26	Japan Population	Easy
27	Population Density Difference	Easy
28	The Blunder	Easy
29	Top Earners	Easy
30	Weather Observation Station 2	Easy
31	Weather Observation Station 13	Easy
32	Weather Observation Station 14	Easy
33	Weather Observation Station 15	Easy
34	Weather Observation Station 16	Easy
35	Weather Observation Station 17	Easy
36	Population Census	Easy
37	African Cities	Easy
38	Average Population of Each Continent	Easy
39	Draw The Triangle 1	Easy
40	Draw The Triangle 2	Easy
41	The PADS	Medium
42	Weather Observation Station 18	Medium
43	Weather Observation Station 19	Medium
44	Binary Tree Nodes	Medium
45	Weather Observation Station 20	Medium
46	The Report	Medium
47	Top Competitors	Medium
48	Ollivander's Inventory	Medium
49	Contest Leaderboard	Medium
50	Placements	Medium
51	New Companies	Medium
52	Challenges	Medium
53	Symmetric Pairs	Medium
54	Print Prime Numbers	Medium
55	Occupations	Medium
56	SQL Project Planning	Medium

2. Databases Problems:

ID	Problem	DIFFICULTY
01	Basics of Sets and Relations #1	Easy
02	Basics of Sets and Relations #2	Easy
03	Basics of Sets and Relations #3	Easy
04	Basics of Sets and Relations #4	Easy
05	Basics of Sets and Relations #5	Easy
06	Basics of Sets and Relations #6	Easy
07	Basics of Sets and Relations #7	Easy
08	Database Normalization #1 - 1NF	Easy
09	Database Normalization #2 - 1/2/3 NF	Easy
10	Database Normalization #3	Hard
11	Database Normalization #4	Easy
12	Database Normalization #5	Medium
13	Database Normalization #6	Medium
14	Database Normalization #7	Medium
15	Database Normalization #8	Medium
16	Database Normalization #9	Hard
17	Database Normalization #10	Medium
18	Databases - Keys	Medium
19	Databases - Natural Joins	Medium
20	Databases - Differences	Medium

3. Python Problems:

ID	Problem	DIFFICULTY
01	Say "Hello, World!" With Python	Easy
02	Python If-Else	Easy
03	Arithmetic Operators	Easy
04	Python: Division	Easy
05	Loops	Easy
06	Write a function	Medium
07	Print Function	Easy
08	List Comprehensions	Easy
09	Find the Runner-Up Score!	Easy
10	Finding the percentage	Easy
11	Lists	Easy
12	Tuples	Easy
13	sWAP cASE	Easy
14	String Split and Join	Easy
15	What's Your Name?	Easy
16	Mutations	Easy
17	Find a string	Easy
18	String Validators	Easy
19	Text Alignment	Easy
20	Text Wrap	Easy
21	Designer Door Mat	Easy
22	Alphabet Rangoli	Easy
23	Nested Lists	Easy
24	Capitalize!	Easy
25	String Formatting	Easy
26	Merge the Tools!	Medium
27	itertools.product()	Easy
28	collections.Counter()	Easy
29	itertools.permutations()	Easy
30	Introduction to Sets	Easy
31	Polar Coordinates	Easy
32	DefaultDict Tutorial	Easy
33	Calendar Module	Easy
34	Exceptions	Easy
35	The Minion Game	Medium
36	combinations_with_replacement()	Easy
37	Collections.namedtuple()	Easy
38	Collections.OrderedDict()	Easy
39	Find Angle MBC	Easy
40	itertools.combinations()	Easy
41	Symmetric Difference	Easy
42	Incorrect Regex	Easy
43	Set .add()	Easy
44	Set .discard(), .remove() & .pop()	Easy
45	Set .union() Operation	Easy
46	Set .intersection() Operation	Easy
47	Set .symmetric_difference() Operation	Easy
48	Set .difference() Operation	Easy
49	Set Mutations	Easy
50	Check Subset	Easy
51	Check Strict Superset	Easy
52	The Captain's Room	Easy
53	No Idea!	Medium
54	Collections.deque()	Easy
55	Piling Up!	Medium
56	Company Logo	Medium
57	Word Order	Medium
58	Integers Come In All Sizes	Easy
59	Power - Mod Power	Easy
60	Mod Divmod	Easy
61	Compress the String!	Medium
62	Iterables and Iterators	Medium
63	Class 2 - Find the Torsional Angle	Easy
64	Input()	Easy
65	Classes: Dealing with Complex Numbers	Medium
66	Zipped!	Easy
67	Python Evaluation	Easy
68	Any or All	Easy
69	ginortS	Medium
70	Athlete Sort	Medium
71	Map and Lambda Function	Easy
72	Reduce Function	Medium
73	Validating Email Addresses With a Filter	Medium
74	Arrays	Easy
75	Shape and Reshape	Easy
76	Transpose and Flatten	Easy
77	Concatenate	Easy
78	Zeros and Ones	Easy
79	Eye and Identity	Easy
80	Array Mathematics	Easy
81	Min and Max	Easy
82	Sum and Prod	Easy
83	Mean, Var, and Std	Easy
84	Linear Algebra	Easy
85	Floor, Ceil and Rint	Easy
86	Polynomials	Easy
87	Inner and Outer	Easy
88	Dot and Cross	Easy
89	Words Score	Medium
90	Standardize Mobile Number Using Decorators	Easy
91	Decorators 2 - Name Directory	Easy
92	XML 1 - Find the Score	Easy
93	Detect Floating Point Number	Easy
94	Re.split()	Easy
95	Group(), Groups() & Groupdict()	Easy
96	Re.findall() & Re.finditer()	Easy
97	Re.start() & Re.end()	Easy
98	Validating Roman Numerals	Easy
99	Validating phone numbers	Easy
100	Validating and Parsing Email Addresses	Easy
101	Hex Color Code	Easy
102	HTML Parser - Part 1	Easy
103	HTML Parser - Part 2	Easy
104	Detect HTML Tags, Attributes and Attribute Values	Easy
105	Validating UID	Easy
106	Validating Credit Card Numbers	Easy
107	Time Delta	Medium

4. Linux Shell Problems:

ID	Problem	DIFFICULTY
01	Let's Echo	Easy
02	Looping and Skipping	Easy
03	A Personalized Echo	Easy
04	Looping with Numbers	Easy
05	The World of Numbers	Easy
06	Comparing Numbers	Easy
07	Getting started with conditionals	Easy
08	More on Conditionals	Easy
09	Head of a Text File #1	Easy
10	Head of a Text File #2	Easy
11	Tail of a Text File #1	Easy
12	Tail of a Text File #2	Easy
13	Cut #1	Easy
14	Cut #2	Easy
15	Cut #3	Easy
16	Cut #4	Easy
17	Cut #5	Easy
18	Cut #6	Easy
19	Cut #7	Easy
20	Cut #8	Easy
21	Cut #9	Easy
22	Middle of a Text File	Easy
23	'Tr' Command #1	Easy
24	'Tr' Command #2	Easy
25	'Tr' Command #3	Easy
26	Sort Command #1	Easy
27	Sort Command #2	Easy
28	Sort Command #3	Easy
29	Sort Command #4	Easy
30	Sort Command #5	Easy
31	Sort Command #6	Easy
32	Sort Command #7	Easy
33	'Uniq' Command #1	Easy
34	'Uniq' Command #2	Easy
35	'Uniq' Command #3	Easy
36	'Uniq' Command #4	Easy
37	Paste - 1	Medium
38	Paste - 2	Medium
39	Paste - 3	Medium
40	Paste - 4	Medium
41	Read in an Array	Easy
42	Slice an Array	Easy
43	Display an element of an array	Easy
44	Count the number of elements in an Array	Easy
45	Concatenate an array with itself	Easy
46	Filter an Array with Patterns	Medium
47	Remove the First Capital Letter from Each Element	Medium
48	'Grep' - A	Easy
49	'Grep' #1	Medium
50	'Grep' #2	Medium
51	'Grep' #3	Medium
52	'Sed' command #1	Medium
53	'Sed' command #2	Medium
54	'Awk' - 1	Medium
55	'Awk' - 2	Medium
56	'Awk' - 3	Medium
57	'Awk' - 4	Medium
58	'Sed' command #3	Easy
59	'Sed' command #4	Hard
60	Compute the Average	Medium