HackerRank Solution

• java
  
• 30 Day of Code
• Problem Solving
• C++

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30 Day of Code

Day	Challenge	Solution	Difficulty	Max Score
0	Hello, World	Solution	Easy	30
1	Data Types	Solution	Easy	30
2	Operators	Solution	Easy	30
3	Intro to Conditional Statements	Solution	Easy	30
4	Class vs. Instance	Solution	Easy	30
5	Loops	Solution	Easy	30
6	Let's Review	Solution	Easy	30
7	Arrays	Solution	Easy	30
8	Dictionaries and Maps	Solution	Easy	30
9	Recursion 3	Solution	Easy	30
10	Binary Numbers	Solution	Easy	30
11	2D Arrays Binary Numbers	Solution	Easy	30
12	Inheritance	Solution	Easy	30
13	Abstract Classes	Solution	Easy	30
14	Scope	Solution	Easy	30
15	Linked List	Solution	Easy	30
16	Exceptions - String to Integer	Solution	Easy	30
17	More Exceptions	Solution	Easy	30
18	Queues and Stacks	Solution	Easy	30
19	Interfaces	Solution	Easy	30
20	Sorting	Solution	Easy	30
21	Generics	Solution	Easy	30
22	Binary Search Trees	Solution	Easy	30
23	BST Level-Order Traversal	Solution	Easy	30
24	More Linked Listsl	Solution	Easy	30
25	Running Time and Complexity	Solution	Medium	30
26	Nested Logic	Solution	Easy	30
27	Testing	Solution	Easy	30
28	RegEx, Patterns, and Intro to Databases	Solution	Medium	30
29	Bitwise AND	Solution	Medium	30

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java

No.	Subdomain	Challenge	Points	Solution	Difficulty
1	Introduction	Welcome to Java!	3	Solution	Easy
2	Introduction	Java Stdin and Stdout I	5	Solution	Easy
3	Introduction	Java If-Else	10	Solution	Easy
4	Introduction	Java Stdin and Stdout II	10	Solution	Easy
5	Introduction	Java Output Formatting	10	Solution	Easy
6	Introduction	Java Loops I	10	Solution	Easy
7	Introduction	Java Loops II	10	Solution	Easy
8	Introduction	Java Datatypes	10	Solution	Easy
9	Introduction	Java End-of-file	10	Solution	Easy
10	Introduction	Java Static Initializer Block	10	Solution	Easy
11	Introduction	Java Int to String	10	Solution	Easy
12	Introduction	Java Date and Time	15	Solution	Easy
13	Introduction	Java Currency Formatter	15	Solution	Easy
14	Strings	Java Strings Introduction	5	Solution	Easy
15	Strings	Java Substring	5	Solution	Easy
16	Strings	Java Substring Comparisons	10	Solution	Easy
17	Strings	Java String Reverse	10	Solution	Easy
18	Strings	Java Anagrams	10	Solution	Easy
19	Strings	Java String Tokens	15	Solution	Easy
20	Strings	Pattern Syntax Checker	20	Solution	Easy
21	Strings	Java Regex	25	Solution	Medium
22	Strings	Java Regex 2 - Duplicate Words	25	Solution	Medium
23	Strings	Valid Username Regular Expression	20	Solution	Medium
24	Strings	Tag Content Extractor	20	Solution	Medium
25	BigNumber	Java BigInteger	10	Solution	Easy
26	BigNumber	Java Primality Test	20	Solution	Easy
27	BigNumber	Java BigDecimal	20	Solution	Medium
28	Data Structures	Java 1D Array	5	Solution	Easy
29	Data Structures	Java 2D Array	10	Solution	Easy
30	Data Structures	java Subarray	10	Solution	Easy
31	Data Structures	Java Arraylist	10	Solution	Easy
32	Data Structures	Java 1D Array (Part 2)	25	Solution	Medium
33	Data Structures	Java List	15	Solution	Easy
34	Data Structures	Java Map	10	Solution	Easy
35	Data Structures	Java Stack	20	Solution	Medium

Problem Solving

problem No.	Subdomain	Challenge	Solution	Difficulty	Max Score
1	Warmup	Solve Me First	Solution	Easy	1
2	Warmup	Simple Array Sum	Solution	Easy	10
3	Warmup	Compare the Triplets	Solution	Easy	10
4	Warmup	A Very Big Sum	Solution	Easy	10
5	Warmup	Diagonal Difference	Solution	Easy	10
6	Warmup	Plus Minus	Solution	Easy	10
7	Warmup	Staircase	Solution	Easy	10
8	Warmup	Mini-Max Sum	Solution	Easy	10
9	Warmup	Birthday Cake Candles	Solution	Easy	10
10	Warmup	Time Conversion	Solution	Easy	15
11	Implementation	Grading Students	Solution	Easy	10

C++

problem No.	Subdomain	Challenge	Solution	Difficulty	Max Score
1	Introduction	Say "Hello, World!" With C++	Solution	Easy	5
2	Introduction	Input and Output	Solution	Easy	5
3	Introduction	Basic Data Types	Solution	Easy	10
4	Introduction	Conditional Statements	Solution	Easy	10
5	Introduction	For Loop	Solution	Easy	10
6	Introduction	Functions	Solution	Easy	10
7	Introduction	Pointr	Solution	Easy	10
8	Introduction	Arrays Introduction	Solution	Easy	10
9	Introduction	Variable Sized Arrays	Solution	Easy	30
10	Strings	StringStream	Solution	Easy	10
11	Strings	String	Solution	Easy	10