 JavaScript Interview PreparationPrepare for an upcoming JavaScript technical interview

Course Material

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• Intermediate Coding Challenges
• Prime Time

For this challenge you will be determining if an argument is a prime number. 12295 solutions

• Run Length

For this challenge you will determine the Run Length Encoding of a string. 8804 solutions

• Prime Mover

For this challenge you will be returning a certain prime number. 7596 solutions

• Palindrome Two

For this challenge you will be determining if a string is a palindrome. 7317 solutions

• Division

For this challenge you will determine the Greatest Common Factor between two numbers. 6782 solutions

• String Scramble

For this challenge you will determine if string 1 can be rearranged into string 2. 7514 solutions

• Arith Geo II

For this challenge you will determine if numbers within an array follow an arithmetic or geometric sequence. 5115 solutions

For this challenge you will determine if numbers in an array can add up to a certain number in the array. 4650 solutions

• Binary Converter

For this challenge you will be converting a number from binary to decimal. 4632 solutions

• Letter Count

For this challenge you will determine which word has the greatest number of repeated letters. 4600 solutions

• Caesar Cipher

For this challenge you will transform a string using the Caesar Cipher. 5296 solutions

• Simple Mode

For this challenge you will determine the mode, the number that appears most frequently, in an array. 5105 solutions

• Consecutive

For this challenge you will determine how to order an array of numbers consecutively. 4233 solutions

• Formatted Division

For this challenge you will divide two numbers and print them in a certain format. 3904 solutions

• Counting Minutes

For this challenge you will return the total number of minutes between two times. 2897 solutions

• Permutation Step

For this challenge you will determine the next greatest number using the same numbers of a given argument. 3442 solutions

• Prime Checker

For this challenge you will determine if you can arrange a number to be a prime number. 2634 solutions

• Dash Insert II

For this challenge you will be manipulating a string using dashes (-). 5037 solutions

• Swap II

For this challenge you will be manipulating numbers in a string based on the characters. 2820 solutions

• Number Search

For this challenge you will traverse a string searching for all the numbers and then you will add them up. 3456 solutions

• Triple Double

For this challenge you will determine if there is a number that appears consecutively in both arguments. 3199 solutions

• Bracket Matcher

For this challenge you will determine if the brackets in a string are correctly matched up. 2911 solutions

• String Reduction

For this challenge you will manipulate a string of characters using a simple reduction method. 2456 solutions

• ThreeFive Multiples

For this challenge you will be determining the multiples of a specific number. 2906 solutions

• Binary Search Tree LCA

For this challenge you will attempt to find the lowest common ancestor of a binary search tree. 367 solutions

• Coin Determiner

For this challenge you will be determining the smallest combination of coins for a given output 2383 solutions

• Fibonacci Checker

For this challenge you will be determining whether a number is part of the Fibonacci sequence. 2710 solutions

• Multiple Brackets

For this challenge you will determine if all the brackets in a string are correctly matched up. 2424 solutions

• Most Free Time

For this challenge you will determine what period of the day gives the most free time. 1519 solutions

• Overlapping Rectangles

For this challenge you will be determining the areas of rectangles. 1664 solutions

• Look Say Sequence

For this challenge you will determine the next number in a sequence. 1530 solutions

• Distinct List

For this challenge you will remove duplicate elements from an array. 2451 solutions

• Number Encoding

For this challenge you will encode a given string following a specific rule. 1537 solutions

• Stock Picker

For this challenge you will determine the maximum profit that can be made in a range of stock prices. 865 solutions

• Max Subarray

For this challenge you will determine the largest sum subarray. 737 solutions

• Missing Digit

For this challenge you will determine what the variable is in a mathematical equation. 491 solutions

• K Unique Characters

For this challenge you will be searching a string for a particular substring. 544 solutions

• Bitmap Holes

For this challenge you will be searching within a 2D matrix. 364 solutions

• Symmetric Tree

For this challenge you will traverse a binary tree and determine if it is symmetric. 318 solutions

• Binary Tree LCA

For this challenge you will attempt to find the lowest common ancestor of a binary tree. 184 solutions

• LRU Cache

For this challenge you will determine the order of elements within a simulated cache. 244 solutions

• Tree Constructor

For this challenge you will determine if an array of integer pairs can form a binary tree properly. 420 solutions

• Array Min Jumps

For this challenge you will determine how quickly you can reach the end of an array. 272 solutions

• Nearest Smaller Values

For this challenge you will determine the nearest smaller value for each number in an array. 469 solutions

• Matrix Spiral

For this challenge you will print a 2D matrix in spiral order. 257 solutions

• Word Split

For this challenge you will attempt to split a long string of characters into actual words. 460 solutions

• Pair Searching

For this challenge you will determine how to multiply a number to find a duplicate pair. 146 solutions

• Boggle Solver

For this challenge you will attempt to find words in a matrix of letters. 117 solutions

• HTML Elements

For this challenge you will determine whether HTML elements are nested correctly. 213 solutions

• Missing Digit II

For this challenge you will determine what the variables are in a mathematical equation. 182 solutions

• Palindromic Substring

For this challenge you will be finding the longest palindromic substring. 306 solutions

• Trapping Water

For this challenge you will determine the largest amount of water you can trap within a boundary. 198 solutions

• Matrix Path

For this challenge you will determine if a path exists in a boolean matrix. 112 solutions

• Seating Students

For this challenge you will determine how many different ways students can sit next to each other. 226 solutions

• Longest Matrix Path

For this challenge you will be searching for the longest path in a 2D matrix. 87 solutions

• Min Window Substring

For this challenge you will be searching for the optimal substring of k characters. 189 solutions

• Matrix Chains

For this challenge you will determine the best order to multiply matrices. 83 solutions

• Histogram Area

For this challenge you will determine the largest area under a histogram. 266 solutions

• Matching Characters

For this challenge you will be determining the largest number of unique characters between two letters. 235 solutions

• Ternary Converter

For this challenge you will be converting a decimal number into ternary. 114 solutions

• Linear Congruence

For this challenge you will be solving a linear congruence equation. 63 solutions

• Formatted Number

For this challenge you will be determining if a string is a valid number. 248 solutions

• Largest Row Column

For this challenge you will be finding the largest sum of three digits in a matrix. 72 solutions

• Eight Queens

This challenge will require knowledge of chess pieces and their movements. 2245 solutions

• Three Points

For this challenge you will be plotting a line on a Cartesian grid. 166 solutions

• Character Removal

For this challenge you will attempt to modify a word and then find it within a dictionary. 199 solutions

For this challenge you will be determining if a string is a valid password. 255 solutions

• Preorder Traversal

For this challenge you will be traversing a binary tree. 128 solutions

• String Zigzag

For this challenge you will be printing a string in a particular zig-zag format. 121 solutions

• Off Binary

For this challenge you will be determining the correct binary number. 108 solutions

• Longest Consecutive

For this challenge you will compute the length of the longest consecutive subsequence. 359 solutions

• String Expression

For this challenge you will convert a string of written numbers to an actual number. 169 solutions

• Charlie the Dog

For this challenge you will be helping a dog collect all the food in a grid. 157 solutions

• Plus Minus

For this challenge you will need to determine how to add or subtract numbers to end up with zero. 207 solutions

• Primes

For this challenge you will be determining if an argument is a prime number. 109 solutions

• String Calculate

For this challenge you will be evaluating a mathematical expression within a string. 75 solutions