ANSWERS TO MERKLE CODING TEST FOR JUNIOR DEVELOPER ROLE.

// SIDENOTE: I USED VANILLA JAVASRIPT ON NODEJS TO ANSWER THIS TEST. PLEASE INSTALL "NODEMON" TO RUN NPM START: TO SEE ANSWERS FOR EACH DOCUMENT.

EACH QUESTION IS ANSWERED IN A SPERATE FILE. //

MERKLE QUESTIONS:

QUESTION ONE: PARTONE.JS

Implement the function longestSequence(sequence)which takes a string of letters and finds the longest sequence where the same letter occurs continuously. The function must return an object literal {c: n} where c is the lowercase character and n is the length of this sub-sequence. If there are multiple characters with a continuous sequence of the same length, return the information for the letter which occurs first alphabetically.

EXAMPLES : longest_sequence( "dghhhmhmx" ) === {h: 3} longest_sequence( "dhkkhhKKKt" ) === {k: 3} longest_sequence( "aBbBadddadd" ) === {b: 3}

QUESTION TWO: PARTTWO.JS

Implement the following function to calculate the current balance of a bank savings account at the end of numMonths (a specific number of months). balance(openingSum, interestRate, taxFreeLimit, taxRate, numMonths)

The calculation must reflect the following assumptions:

• openingSum is the initial account balance. • Every month, the monthly interest is calculated as interestRate percent of the account balance available at the beginning of each month. • Every month, the monthly tax is calculated as taxRate percent of (account balance - taxFreeLimit) if the account balance is greater than the allowed taxFreeLimit. Otherwise, the monthly tax is 0.

At the end of each month, the balance is updated by adding the monthly interest and subtracting the monthly tax.

EXAMPLES: balance(10000, 1, 20000, 1, 2) #must be approximately 10201 balance(25000, 2, 20000, 1, 2) #must be approximately 25904.5 balance(19800, 2, 20000, 1, 2) #must be approximately 20597.96

QUESTION THREE: PARTTHREE.JS

Implement a function reverseString(string) which accepts a string parameter, reverses it and returns it. Do not use .reverse() or any other standard JavaScript string functions or sorting functions. Do not use loops or iteration. Use the following ideas to implement the function recursively:

• if the string is empty, its reverse is the empty string • if the string has one character, return it • otherwise, the result is a concatenation of the string parameter without the first letter, in reverse, and the first letter at the end

EXAMPLES: reverseString( “abcb” ) === “bcba” reverseString( “test” ) === “tset” reverseString( “racecar” ) === “racecar”

QUESTION FOUR: PARTFOUR.JS

Implement a class called Time. The following class variables should be initialised as integers in the class constructor (or init method in Python): hours minutes seconds

Include a method which normalises the time and invoke it appropriately so that the time is automatically adjusted when large integers are passed in. The following rules should remain true: 0 <= hours <= 23 0 <= minutes <= 59 0 <= seconds <= 59

Include a method called scale which will accept an integer of seconds and add it to the time held in the current instance. Include a method called timeString which returns a string in the format “hh:mm:ss.

EXAMPLES: Time t = new Time( 1, 30, 20 ); t.timeString() == “01:30:20” t.scale( 400 ); t.timeString() == “01:37:00”

Time t = new Time( 1, 100, 0 ); t.timeString() == “02:40:00”