JavaScript Coding Challenges

01. Creates a function that takes two numbers as arguments and return their sum.

functionaddition(a,b){//Write Your solution Here};console.log(addition(10,20));// 30console.log(addition(30,20));// 50console.log(addition(10,90));// 100

02. Converts hours into seconds.

functionhowManySeconds(hours){//Write Your solution Here};console.log(howManySeconds(12));// 43200console.log(howManySeconds(8));// 28800console.log(howManySeconds(3));// 10800

03. Converts minutes into seconds.

functionconvert(minutes){//Write Your solution Here};console.log(convert(30));// 1800console.log(convert(10));// 600console.log(convert(20));// 1200

04. Calculates total points of a team from number of wins(3pts), draws(1pt), and losses(0pt).

functionfootballPoints(wins,draws,losses){//Write Your solution Here};console.log(footballPoints(4,3,1));// 15console.log(footballPoints(10,5,0));// 35console.log(footballPoints(11,0,9));// 33

05. Write functions to calculate the bitwise AND, bitwise OR and bitwise XOR of two numbers.

functionbitwiseAND(n1,n2){//Write Your solution Here};functionbitwiseOR(n1,n2){//Write Your solution Here};functionbitwiseXOR(n1,n2){//Write Your solution Here};console.log(bitwiseAND(10,20));// 0console.log(bitwiseOR(10,20));// 30console.log(bitwiseXOR(10,20));// 30

06. Write Function to return first value of an array.

functiongetFirstValue(arr){//Write Your solution Here};console.log(getFirstValue(["Saab","Volvo","BMW"]));// Saabconsole.log(getFirstValue([3,5,1]));// 3console.log(getFirstValue(['hello','world','welcome']));// hello

07. Create a function that takes a number as an argument, increments the number by +1 and returns the result.

functionaddition(num){//Write Your solution Here};console.log(addition(5));// 6console.log(addition(100));// 101console.log(addition(99));// 100

08. Given two numbers, return true if the sum of both numbers is less than 100. Otherwise return false.

functionlessThan100(a,b){//Write Your solution Here};console.log(lessThan100(10,20));// trueconsole.log(lessThan100(50,60));// falseconsole.log(lessThan100(20,50));// true

09. Create a function that returns true when num1 is equal to num2; otherwise return false.

functionisSameNum(num1,num2){//Write Your solution Here};console.log(isSameNum(30,30));// trueconsole.log(isSameNum(20,40));// falseconsole.log(isSameNum(50,50));// true

10. Create a function that takes a number (step) as an argument and returns the amount of matchsticks in that step.

functionmatchHouses(step){//Write Your solution Here};console.log(matchHouses(5));// 26console.log(matchHouses(0));// 0console.log(matchHouses(10));// 51

11. Write function to return the square of a number.

functionsquared(a){//Write Your solution Here};console.log(squared(6));// 36console.log(squared(9));// 81console.log(squared(4));// 16

12. Write function to calculate Perimeter of Rectangles

functionfindPerimeter(height,width){//Write Your solution Here};console.log(findPerimeter(20,50));// 140console.log(findPerimeter(80,30));// 220console.log(findPerimeter(10,40));// 100

13. Add up all the numbers from 1 to the number you passed to the function.

functionaddUp(num){//Write Your solution Here};console.log(addUp(10));// 55console.log(addUp(40));// 820console.log(addUp(15));// 120

14. Create a function that takes in three arguments (prob, prize, pay) and returns true if prob * prize > pay; otherwise return false.

functionprofitableGamble(prob,prize,pay){//Write Your solution Here};console.log(profitableGamble(2,10,20));// falseconsole.log(profitableGamble(5,10,40));// trueconsole.log(profitableGamble(6,3,30));// false

15. Takes an array of numbers, returns both the minimum and maximum numbers, in that order.

functionminMax(arr){//Write Your solution Here};console.log(minMax([2,-1,5]));// [ -1, 5 ]console.log(minMax([0,5,2]));// [ 0, 5 ]console.log(minMax([2,-5,-1]));// [ -5, 2 ]

16. Create a function that returns true if the first array can be nested inside the second.

arr1 can be nested inside arr2 if:

arr1's min is greater than arr2's min.

arr1's max is less than arr2's max.

functioncanNest(arr1,arr2){//Write Your solution Here};console.log(canNest([3,1],[4,0]));// trueconsole.log(canNest([9,9,8],[8,9]));// falseconsole.log(canNest([1,2,3,4],[0,6]));// true

17. Create a function that calculates the number of different squares in an n * n square grid.

functionnumberSquares(n){//Write Your solution Here};console.log(numberSquares(4));// 30console.log(numberSquares(5));// 55console.log(numberSquares(6));// 91

18. Your function will be passed two functions, f and g, that don't take any parameters. Your function has to call them, and return a string which indicates which function returned the larger number.

If f returns the larger number, return the string f.

If g returns the larger number, return the string g.

If the functions return the same number, return the string neither.

functionwhichIsLarger(f,g){//Write Your solution Here};console.log(whichIsLarger(()=>25,()=>15));// fconsole.log(whichIsLarger(()=>25,()=>25));// neitherconsole.log(whichIsLarger(()=>25,()=>50));// g

19. Christmas Eve is almost upon us, so naturally we need to prepare some milk and cookies for Santa! Create a function that accepts a Date object and returns true if it's Christmas Eve (December 24th) and false otherwise. Keep in mind JavaScript's Date month is 0 based, meaning December is the 11th month while January is 0.

functiontimeForMilkAndCookies(date){//Write Your solution Here};console.log(timeForMilkAndCookies(newDate(3000,11,24)));//trueconsole.log(timeForMilkAndCookies(newDate(2013,0,23)));//falseconsole.log(timeForMilkAndCookies(newDate(3000,11,24)));//true

20. function that takes a two-digit number and determines if it's the largest of two possible digit swaps.

functionlargestSwap(num){//Write Your solution Here};console.log(largestSwap(14));//falseconsole.log(largestSwap(53));//trueconsole.log(largestSwap(-27));//false

21. function that takes two strings as arguments and returns the number of times the first string (the single character) is found in the second string.

functioncharCount(myChar,str){//Write Your solution Here};console.log(charCount("a","largest"));//1console.log(charCount("c","Chamber of secrets"));// 2console.log(charCount("b","big fat bubble"));//4

22. function that takes two parameters and repeats the string n number of times.

functionrepetition(txt,n){//Write Your solution Here};console.log(repetition('zim',5));//zimzimzimzimzimconsole.log(repetition('zoy',2));//zoyzoyconsole.log(repetition('akib',7));//akibakibakibakibakibakibakib

23. function that takes an array of non-negative integers and strings and return a new array without the strings.

functionfilterArray(arr){//Write Your solution Here};console.log(filterArray([1,'z',4,5,'i',9,'m']));//[ 1, 4, 5, 9 ]console.log(filterArray([8,'z',1,'8','i',9,'m']));//[ 8, 1, 9 ]console.log(filterArray([7,'1','z',0,'i',9,'m']));//[ 7, 0, 9 ]

24. Write a function that take a string and write a regular expression inner function that returns the value that matches every red flag and blue flag in this string.

functionmatchFlag(str){//Write Your solution Here};console.log(matchFlag("yellow flag red flag blue flag green flag"));//[ 'red flag', 'blue flag' ]console.log(matchFlag("yellow flag green flag orange flag white flag"));//nullconsole.log(matchFlag("yellow flag blue flag green flag"));//[ 'blue flag' ]

25. Write a function that take a string and write a RegExp to find ellipsis: 3 (or more?) dots in a row in this string.

functionmatchEllipsis(str){//Write Your solution Here};console.log(matchEllipsis("Hello!... How goes?....."));//[ '...', '.....' ]console.log(matchEllipsis("good morning!..... How goes?."));// [ '.....' ]console.log(matchEllipsis("good night!.......... How goes?..."));// [ '..........', '...' ]

26. Write a function that returns 0 if the input is 1, and returns 1 if the input is 0. Try completing this challenge without using any:

Conditionals

Ternary operators

Negations

Bit operators

functionflip(y){//Write Your solution Here};console.log(flip(1));// 0console.log(flip(0));// 1

27. Create a function that takes a string and returns a string in which each character is repeated once.

functiondoubleChar(str){//Write Your solution Here};console.log(doubleChar('jahidul'));//jjaahhiidduullconsole.log(doubleChar('islam'));//iissllaammconsole.log(doubleChar('zim'));//zziimm

28. Write a function that takes a positive integer and return its factorial.

functionfactorial(num){//Write Your solution Here};console.log(factorial(5));//120console.log(factorial(10));//3628800console.log(factorial(8));//40320

29. Take an array of integers (positive or negative or both) and return the sum of the absolute value of each element.

functiongetAbsSum(arr){//Write Your solution Here};console.log(getAbsSum([1,-4,3,8,0]));// 16console.log(getAbsSum([1,3,0,-8,0]));// 12console.log(getAbsSum([1,-4,-3,8,0]));//16

30. Write a function that take a string and write a REGEXP that matches any characters except letters, digits and spaces.

functionmatchAny(str){//Write Your solution Here};console.log(matchAny('Csxdzontains_underscore '));//[ '_' ]console.log(matchAny('Csxdzontains_underscore $ * P'));//[ '_', '$', '*' ]

31. Create a function that takes a string and returns the number (count) of vowels contained within it.

functioncountVowels(str){//Write Your solution Here};console.log(countVowels('Jahidul Islam zim'));// 6console.log(countVowels('returns the number of vowels'));// 8console.log(countVowels('JavaScript Coding Challenges'));// 8

32. Create a function that takes two vectors as arrays and checks if the two vectors are orthogonal or not. The return value is boolean. Two vectors a and b are orthogonal if their dot product is equal to zero.

functionisOrthogonal(arr1,arr2){//Write Your solution Here};console.log(isOrthogonal([1,-2,4],[2,5,2]));//trueconsole.log(isOrthogonal([1,-2,5],[2,5,2]));//falseconsole.log(isOrthogonal([1,2,4],[-2,5,-2]));//true

33. Given an object of how many more pages each ink color can print, output the maximum number of pages the printer can print before any of the colors run out.

functioninkLevels(inks){//Write Your solution Here};console.log(inkLevels({cyan:50,magenta:12,yellow:60}));// 12console.log(inkLevels({cyan:50,magenta:120,yellow:60}));// 50console.log(inkLevels({cyan:50,magenta:12,yellow:8}));// 8

34. Create a function that takes a string and returns a new string with all vowels removed.

functionremoveVowels(str){//Write Your solution Here};console.log(removeVowels('Jahidul Islam Zim'));//Jhdl slm Zmconsole.log(removeVowels('a new string with all vowels'));// nw strng wth ll vwlsconsole.log(removeVowels('Create a function'));//Crt  fnctn

35. Create a function that takes an array of arrays with numbers. Return a new (single) array with the largest numbers of each.

functionfindLargestNums(arr){//Write Your solution Here};console.log(findLargestNums([[3,6],[10,20],[-1,7]]));//[ 6, 20, 7 ]console.log(findLargestNums([[8,6],[1,0],[10,-7]]));//[ 8, 1, 10 ]console.log(findLargestNums([[3,34],[10,22],[-1,-7]]));//[ 34, 22, -1 ]

36. Given an array of scrabble tiles, create a function that outputs the maximum possible score a player can achieve by summing up the total number of points for all the tiles in their hand. Each hand contains 7 scrabble tiles.

functionmaximumScore(tileHand){//Write Your solution Here};console.log(maximumScore([{tile:"N",score:1},{tile:"K",score:5},{tile:"Z",score:10},]));//16console.log(maximumScore([{tile:"N",score:9},{tile:"K",score:5},{tile:"Z",score:40},]));//54console.log(maximumScore([{tile:"N",score:1},{tile:"K",score:65},{tile:"Z",score:10},]));//76

37. Assume a program only reads .js or .jsx files. Write a function that accepts a file path and returns true if it can read the file and false if it can't.

functionisJS(path){//Write Your solution Here};console.log(isJS('file.jsx'));//trueconsole.log(isJS('file.jsg'));//falseconsole.log(isJS('file.js'));//true

38. A farmer is asking you to tell him how many legs can be counted among all his animals. The farmer breeds three species:

chickens = 2 legs

cows = 4 legs

goats = 4 legs

The farmer has counted his animals and he gives you a subtotal for each species. You have to implement a function that returns the total number of legs of all the animals.

functionanimals(chickens,cows,goats){//Write Your solution Here};console.log(animals(2,3,5))// 36console.log(animals(1,2,3))// 22console.log(animals(5,2,8))// 50

39.Create a function that returns the number of frames shown in a given number of minutes for a certain FPS.

FPS = Frames Per Second

functionframes(minutes,fps){//Write Your solution Here};console.log(frames(1,1));//60console.log(frames(10,1));//600console.log(frames(10,25));//15000

40.Create a function that takes two arguments. Both arguments are integers, a and b. Return true if one of them is 10 or if their sum is 10.

functionmakesTen(a,b){//Write Your solution Here};console.log(makesTen(1,1));//60console.log(makesTen(10,1));//600console.log(makesTen(10,25));//15000

41.Create a function that takes two strings as arguments and return either true or false depending on whether the total number of characters in the first string is equal to the total number of characters in the second string.

functioncomp(str1,str2){//Write Your solution Here};console.log(comp("AB","CD"));//trueconsole.log(comp("ABC","DE"));//falseconsole.log(comp("WE","RT"));// true

42.A vehicle needs 10 times the amount of fuel than the distance it travels. However, it must always carry a minimum of 100 fuel before setting off. Create a function which calculates the amount of fuel it needs, given the distance.

functioncalculateFuel(n){//Write Your solution Here};console.log(calculateFuel(15));//150console.log(calculateFuel(23.5));//235console.log(calculateFuel(3));//100

43.Given an n-sided regular polygon n, return the total sum of internal angles (in degrees). n will always be greater than 2.

The formula (n - 2) x 180 gives the sum of all the measures of the angles of an n-sided polygon.

functionsumPolygon(n){//Write Your solution Here};console.log(sumPolygon(3));//180console.log(sumPolygon(4));//360console.log(sumPolygon(6));// 720

44.Create a function that returns true if an integer is evenly divisible by 5, and false otherwise.

functiondivisibleByFive(n){//Write Your solution Here};console.log(divisibleByFive(5));//trueconsole.log(divisibleByFive(-55));//falseconsole.log(divisibleByFive(37));//true

45. Create a function that takes in an array of numbers and returns the sum of its cubes.

functionsumOfCubes(nums){//Write Your solution Here};console.log(sumOfCubes([1,2,3,4,5]));//255console.log(sumOfCubes([5,2,7,4,0]));//540console.log(sumOfCubes([1,6,3,9,5]));//1098

46.A group of friends have decided to start a secret society. The name will be the first letter of each of their names, sorted in alphabetical order. Create a function that takes in an array of names and returns the name of the secret society.

functionsocietyName(friends){//Write Your solution Here};console.log(societyName(['zim','zoy','shithil','akib']));//zzsaconsole.log(societyName(['Rakib','Taskin','shomrat','Prionty']));//RTsPconsole.log(societyName(['Ratul','Rakib','Ritu','Taj']));//RRRT

47. Create two functions: isPrefix(word, prefix-) and isSuffix(word, -suffix).

isPrefix should return true if it begins with the prefix argument.

isSuffix should return true if it ends with the suffix argument.

Otherwise return false.

functionisPrefix(word,prefix){//Write Your solution Here};functionisSuffix(word,suffix){//Write Your solution Here};console.log(isPrefix("automation","auto-"));//trueconsole.log(isPrefix("retrospect","sub-"));//falseconsole.log(isSuffix("arachnophobia","-phobia"));//trueconsole.log(isSuffix("vocation","-logy"));//false

48. Create a function that returns the number of hashes and pluses in a string.

functionhashPlusCount(str){//Write Your solution Here};console.log(hashPlusCount("###+"));//[ 3, 1 ]console.log(hashPlusCount("##+++#"));//[ 3, 3 ]console.log(hashPlusCount(""));//[ 0, 0 ]

49. Create a function that takes an array of 10 numbers (between 0 and 9) and returns a string of those numbers formatted as a phone number (e.g. (555) 555-5555).

functionformatPhoneNumber(numbers){//Write Your solution Here};console.log(formatPhoneNumber([1,2,3,4,5,6,7,8,9,0]));//(123) 456-7890console.log(formatPhoneNumber([1,2,0,4,5,3,8,1,9,0]));//(120) 453-8190console.log(formatPhoneNumber([1,7,9,4,2,6,8,8,5,0]));//(179) 426-8850

50. Write a regular expression that matches only an even number. Numbers will be presented as strings.

functionmatchEven(str){//Write Your solution Here};console.log(matchEven("3458"));//8console.log(matchEven("3517"));//Undefinedconsole.log(matchEven("4902"));//2

51. Create a function that returns the index of the first vowel in a string.

functionfirstVowel(str){//Write Your solution Here};console.log(firstVowel("zimislam"));//1console.log(firstVowel("akib"));//0console.log(firstVowel("shomrat"));//2

52. Create a function that removes all duplicate items from an array.

functionremovesDuplicateItems(arr){//Write Your solution Here};console.log(removesDuplicateItems(["A","B","A","C","D","C"]));//[ 'A', 'B', 'C', 'D' ]console.log(removesDuplicateItems([1,4,2,3,2,4,3,5]));//[ 1, 4, 2, 3, 5 ]console.log(removesDuplicateItems(["zim","zoy","zim","akib","shithil","akib"]));//[ 'zim', 'zoy', 'akib', 'shithil' ]

53. Create a function that takes an array of numbers and returns a new array, sorted in ascending order (smallest to biggest).

functionsortNumsAscending(arr){//Write Your solution Here};console.log(sortNumsAscending([2,4,6,1,9,3,5,8,7,0]));//[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]console.log(sortNumsAscending([22,40,56,11,90]));//[ 11, 22, 40, 56, 90 ]console.log(sortNumsAscending([26,45,64,19,59,31]));//[ 19, 26, 31, 45, 59, 64 ]

54. Given a higher bound num, implement a function that returns an array with the sequence of numbers, after that every multiple of 4 has been amplified by 10.

functionamplify(num){//Write Your solution Here};console.log(amplify(12));//[1,   2,  3, 40,  5, 6, 7, 80,  9, 10, 11, 120]console.log(amplify(8));//[1, 2, 3, 40, 5, 6, 7, 80 ]console.log(amplify(15));//[1,  2,  3, 40,  5, 6, 7, 80,  9, 10, 11, 120,13, 14, 15]

55. Given an array of 10 numbers, return the maximum possible total made by summing just 5 of the 10 numbers.

functionmaxTotal(nums){//Write Your solution Here};console.log(maxTotal([1,1,0,1,3,10,10,10,10,1]));//43console.log(maxTotal([0,0,0,0,10,0,3,0,100]));// 113console.log(maxTotal([1,2,3,2,5,6,9,8,9,10]));//42

56. Write a regular expression that matches a string if and only if it is a valid zip code.

Must only contain numbers (no non-digits allowed).

Must not contain any spaces.

Must not be greater than 5 digits in length.

functionisValidZip(zip){//Write Your solution Here};console.log(isValidZip("393939"));//falseconsole.log(isValidZip("59001"));//trueconsole.log(isValidZip("853a7"));//false

57. Create a function that takes a number as an argument and returns the highest digit in that number.

functionhighestDigit(number){//Write Your solution Here};console.log(highestDigit(3456));//6console.log(highestDigit(21098));//9console.log(highestDigit(56123));//6

58. Create a function that takes a number as an argument and returns the highest digit in that number.

functionhighestDigit(number){//Write Your solution Here};console.log(highestDigit(3456));//6console.log(highestDigit(21098));//9console.log(highestDigit(56123));//6

59. Given an array of scrabble tiles, create a function that outputs the maximum possible score a player can achieve by summing up the total number of points for all the tiles in their hand. Each hand contains 7 scrabble tiles.

functionmaximumScore(titleHand){//Write Your solution Here};console.log(maximumScore([{tile:"B",score:2},{tile:"V",score:4},{tile:"F",score:4},{tile:"U",score:1},{tile:"D",score:2},{tile:"O",score:1},{tile:"U",score:1}]));// 15console.log(maximumScore([{tile:"N",score:1},{tile:"K",score:5},{tile:"Z",score:10},{tile:"X",score:8},{tile:"D",score:2},{tile:"A",score:1},{tile:"E",score:1}]));// 28

60.Create a function that takes an array as an argument and returns true or false depending on whether the average of all elements in the array is a whole number or not.

constisAvgWhole=(arr)=>{//Write Your solution Here};console.log(isAvgWhole([1,3]));// trueconsole.log(isAvgWhole([1,2,3,4]));// falseconsole.log(isAvgWhole([1,5,6]));// trueconsole.log(isAvgWhole([1,1,1]));// trueconsole.log(isAvgWhole([9,2,2,5]));// false