Javascript interview logical questions -Very Easy

In recent years, the javascript is more advanced and there are lots of opportunities for javascript developers in the market, but cracking the Javascript interview is sometimes a bit tricky. So you need to prepare yourself from the basic building blocks to advanced javascript features. I have prepared a list of some javascript logical questions which you might get asked in your javascript interview. Try to solve these questions by yourself in a minimum line of code, I have also added the answers for each question on my Github repository(You will find an answer link after each question).

Photo by matthew Feeney on Unsplash

1. Return the Sum of Two Numbers

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

Examples:

addition(3, 2) ➞ 5

addition(-3, -6) ➞ -9

addition(7, 3) ➞ 10

2. Convert Minutes into Seconds

Write a function that takes an integer minutes and converts it to seconds.

Examples

convert(10) ➞ 600

convert(3) ➞ 180

convert(2) ➞ 120

3. Less Than 100?

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

Examples

lessThan100(25, 25) ➞ true  
// 25+ 25= 50

lessThan100(90, 15) ➞ false  
// 90+ 15= 105

lessThan100(30, 27) ➞ true

4. Are the Numbers Equal?

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

Examples

isSameNum(4, 2) ➞ false

isSameNum(7, 7) ➞  true

isSameNum(4, "4") ➞ false

5. Is the String Empty?

Create a function that returns true if a string is empty and false otherwise.

Examples

isEmpty("") ➞ true

isEmpty("z") ➞ false

isEmpty(" ") ➞ false

6. Return a String as an Integer

Create a function that takes a string and returns it as an integer.

Examples

stringInt("7") ➞ 7

stringInt("10") ➞ 10

stringInt("987") ➞ 987

7. Solve the Equation

Create a function that takes an equation (e.g. "1+1"), and returns the answer.

Examples

equation("3+1") ➞ 4

equation("4*4-1") ➞ 15

equation("1+2+3") ➞ 6

8. Reverse an Array

Write a function to reverse an array.

Examples

reverse([1, 2, 3, 4, 5]) ➞ [5, 4, 3, 2, 1]

reverse([9, 2, 1, 5]) ➞ [5, 1, 2, 9]

reverse([]) ➞ []

9. Return the Last Element in an Array

Create a function that accepts an array and returns the last item in the array.

Examples

getLastItem([1, 2, 3, 4]) ➞ 4

getLastItem(["horse", "elephant", "dog"]) ➞ "dog"

getLastItem([true, false ]) ➞ false

10. Find the Index

Create a function that takes an array and a string as arguments and return the index of the string.

Examples

findIndex(["hi", "edabit", "fgh", "abc"], "fgh") ➞ 2

findIndex(["Red", "blue", "Blue", "Green"], "blue") ➞ 1

findIndex(["a", "g", "y", "d"], "d") ➞ 3

findIndex(["Pineapple", "Orange", "Grape", "Apple"], "Pineapple") ➞ 0

11. Check if an Array Contains a Given Number

Write a function to check if an array contains a particular number.

Examples

check([1, 2, 3, 4, 5], 4) ➞ true

check([1, 1, 2, 1, 1], 3) ➞ false

check([5, 5, 5, 6], 5) ➞ true

check([], 5) ➞ false

12. Concatenating First and Last Character of a String

Creates a function that takes a string and returns the concatenated first and last character.

Examples

firstLast("ganesh") ➞ "gh"

firstLast("kali") ➞ "ki"

firstLast("shiva") ➞ "sa"

firstLast("vishnu") ➞ "vu"

firstLast("durga") ➞ "da"

13. Return the Total Number of Parameters

Create a function that returns the total number of parameters passed in.

Examples

numberArgs("a", "b", "c") ➞ 3

numberArgs(10, 20, 30, 40, 50) ➞ 5

numberArgs(x, y) ➞ 2

numberArgs() ➞ 0

14. Multiply Every Array Item by Two

Create a function that takes an array with numbers and return an array with the elements multiplied by two.

Examples

getMultipliedArr([2, 5, 3, 4]) ➞ [4, 10, 6, 8]

getMultipliedArr([1, 86, -5, 5]) ➞ [2, 172, -10, 10]

getMultipliedArr([5, 382, 0]) ➞ [10, 764, 0]

15. Spaces Between Each Character

Create a function that takes a string and returns a string with spaces in between all of the characters.

Examples

spaceMeOut("space") ➞ "s p a c e"

spaceMeOut("far out") ➞ "f a r  o u t"

spaceMeOut("elongated musk") ➞ "e l o n g a t e d   m u s k"

16. Get the Sum of All Array Elements

Create a function that takes an array and returns the sum of all numbers in the array.

Examples

getSumOfItems([2, 5, 3]) ➞ 10

getSumOfItems([45, 3, 10]) ➞ 58

getSumOfItems([-2, 84, 20]) ➞ 102

17. Modifying the Last Character

Create a function which makes the last character of a string repeat n number of times.

Examples

modifyLast("Hello", 3) ➞ "Hellooo"

modifyLast("hey", 6) ➞ "heyyyyyy"

modifyLast("excuse me what?", 5) ➞ "excuse me what?????"

18. Return the First and Last Elements in an Array

Create a function that takes an array of numbers and return the first and last elements as a new array.

Examples

firstLast([5, 10, 15, 20, 25]) ➞ [5, 25]

firstLast(["edabit", 13, null, false, true]) ➞ ["edabit", true]

firstLast([undefined, 4, "6", "hello", null]) ➞ [undefined, null]

19. Check String for Spaces

Create a function that returns true if a string contains any spaces.

Examples

hasSpaces("hello") ➞ false

hasSpaces("hello world") ➞ true

hasSpaces(" ") ➞ true

hasSpaces("") ➞ false

hasSpaces(",./!@#") ➞ false

20. Case Insensitive Comparison

Write a function that validates whether two strings are identical. Make it case insensitive.

Examples

match("hello", "hELLo") ➞ true

match("motive", "emotive") ➞ false

match("venom", "VENOM") ➞ true

match("mask", "mAskinG") ➞ false

21. Multiply Every Array Item by Two

Create a function that takes a string and returns it as an integer.

Examples

stringInt("6") ➞ 6

stringInt("1000") ➞ 1000

stringInt("12") ➞ 12

22. Filter Strings from Array

Create a function that takes an array of strings and numbers, and filters out the array so that it returns an array of integers only.

Examples

filterArray([1, 2, 3, "a", "b", 4]) ➞ [1, 2, 3, 4]

filterArray(["A", 0, "Edabit", 1729, "Python", "1729"]) ➞ [0, 1729]

filterArray(["Nothing", "here"]) ➞ []

23. Sum of the Odd Numbers

Create a function which returns the total of all odd numbers up to and including n. n will be given as an odd number.

Examples

addOddToN(5) ➞ 9  
// 1 + 3 + 5 = 9

addOddToN(13) ➞ 49

addOddToN(47) ➞ 576

24. Find the Total Number of Digits the Given Number Has

Create a function that takes a number as an argument and returns the amount of digits it has.

Examples

findDigitAmount(123) ➞ 3

findDigitAmount(56) ➞ 2

findDigitAmount(7154) ➞ 4

findDigitAmount(61217311514) ➞ 11

findDigitAmount(0) ➞ 1

25. Convert Number to Corresponding Month Name

Create a function that takes a number (from 1 to 12) and returns its corresponding month name as a string. For example, if you’re given 3 as input, your function should return "March", because March is the 3rd month.

Examples

monthName(3) ➞ "March"

monthName(12) ➞ "December"

monthName(6) ➞ "June"

I have faced these questions while interviewing in many companies, Some of the questions are referenced from internet sites like toptal.com, thatjsdude.com, fullstack.cafe, edabit.com.

Heads Up: I am working on one of the cool Chrome extensions which helps to format your code easily & it’s superfast It can format your code within milliseconds. on top of it, it’s completely free for use. So go & hit that Add to Chrome Button. https://chrome.google.com/webstore/detail/code-formatter/njpgcnaadikbannefjibknjopmogeidm