jindulys/hackerranksolutions

This is a repo for HackerRankSolutions with Swift

HackerRankSolutions

This is a repo for HackerRank Solutions in Swift

Different folders are named after corresponding domain names or contest names.

Algorithms

Problem	Time	Space	Difficulty	Tag	Note	Score	Max Score
Angry Professor	O(n)		Easy	Implementation		20.0	20.0
SherlockAndTheBeast	O(n)		Easy	Implementation		30.0	30.0
Utopian Tree	O(n)		Easy	Implementation		20.0	20.0
Find Digits	O(n)		Easy	Implementation		25.0	25.0
Funny String	O(n)		Easy	String		25.0	25.0
Pangrams	O(n)	O(1)	Easy	String		20.0	20.0
Alternating Characters	O(n)	O(1)	Easy	String		20.0	20.0
Game of Thrones	O(n)	O(1)	Easy	String		30.0	30.0
Make it anagram	O(n)	O(1)	Easy	String		30.0	30.0
Anagram	O(n)	O(1)	Easy	String		14.29	25
Two Strings	O(n)	O(1)	Moderate	String	Set	20.0	25.0
SherlockAndAnagrams	O(n^3lgn)	O(n^2)	Moderate	String	Sort, Dictionary, Permutation	4.55	50.0
Palindrome Index	O(n)	O(1)	Easy	String		25.0	25.0
Sherlock And Valid String	O(n)	O(1)	Difficult	String	Dictionary	100.0	100.0
Common Child	O(n^2)	O(n^2)	Difficult	String	Dynamic Programming	50.0	60.0
The Maximum Subarray	O(n)	O(n)	Easy	Dynamic Programming		16.67	50.0
The Coin Change Problem	O(MN)	O(MN)	Medium	Dynamic Programming	bottom-up table construction	60.0	60.0
Red John is Back	O(N) + O(nlgn)	O(N)	Moderate	Dynamic Programming	memoization	54.17	65
Knapsack	O(MN)	O(MN)	Moderate	Dynamic Programming	memoization in swift	54.06	60.0
Sam and SubStrings	O(N)	O(N)	Moderate	Dynamic Programming		40.0	40.0
The Longest Increasing Subsequence	O(N^2)	O(N)	Advanced	Dynamic Programming	time out	26.67	60.0
Hexagonal Gird	O(N^2)	O(N)	Moderate	Dynamic Programming	recursive solution	70.0	70.0
Sherlock and Cost	O(N)	O(N)	Moderate	Dynamic Programming		28.13	50.0
Dorsey Thief	O(NM)	O(NM)	Advanced	Dynamic Programming		52.76	85.0
Travel Around the World	O(N)	O(N)	Moderate	Dynamic Programming	validation pass and candidates finding pass	120.0	120.0
Sherlock and Array	O(N)	O(N)	Easy	Search		40.0	40.0
Ice Cream Parlor	O(N)	O(N)	Easy	Search		30.0	30.0
Maximise Sum	O(N)	O(NlgN)	Moderate	Search		20.31	65.0
Missing Number	O(N)	O(N)	Moderate	Search	Do you believe 0.59s overtime?	25.99	45

Contests

• IndeedPrimeCodeSprint
• ZenefitsCodeSprint

Data Structures in HackerRankHelper

• FIFO Queue with Two Arraies
• FIFO Queue with Listnode
• ListNode
• AVLNode
• AVLTree
• BinaryIndexedTree
• Heap

Usage

I created class for each problem. If you want to test those solution on HackerRank, please follow this guideline.

1. create a constant with class name.

let mySolution = MyClass()

2. call solution method on that constant

mySolution.solution()

3. copy and paste related helper methods from HackerRankHelper folder, eg. getLine(), getInt()

Swift Package Manager

If you want to use this module to play with local test files, you might need to import this module. Swift Package Manager is a good tool.

Firstly, add following Package.swift to your root directory.

import PackageDescription

let package = Package(
    name:"YourModuleName",
    dependencies: [
        .Package(url:"https://github.com/jindulys/HackerRankSolutions.git", majorVersion:1),
    ]
)

Secondly, when you use this module in your source file, you should:

import HRSwift

Then run swift build, and .build/debug/YourModuleName, Alright, Run!!

Contribution Guidelines

HackerRank lover, swift lover do not hesitate. There are tons of unsolved questions. If you want to contribute a little bit, please write your own swift solutions then make a pull request.

For each question, you should write your own Class in corresponding file, inside that Class define a solution method, which is used for Hackerrank submission. This module could be imported by other packages, so make your class and those usable methods public. If you want to submit solution of Algorithms --> Strings --> Gemstones, you should write your solution inside String.swift. If there is no related file for a subdomain, please create a new file.

Write a test case in HRSwiftTests.swift. You could use sample input and sample output from that question as a test.

 func testAnagram() {
     let test = Anagram()
     XCTAssert(test.solve("aaabbb") == 3, "Pass")
     XCTAssert(test.solve("ab") == 1, "Pass")
     XCTAssert(test.solve("abc") == -1, "Pass")
 }

If you write some general code that could be used afterwards, please write them in HackerRankHelper

Make sure your solution get a reasonable score on HackerRank then pull request.

You should obey Raywenderlich Swift Style Guide

hackerranksolutions's Issues

Objective C support

1. Can you provide the code in objective c too.
2. I have one code in php. Can you convert it to Objective C.

Thanks

Red John is Back

@jindulys I found bug in your Red John is Back solution.

You need to change method getBetterPrimes

replace
if length < 3 { return primes }

with
if length < 2 { return primes }