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Course Material

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• Practice Challenges
• First Reverse

For this challenge you will be reversing a string. 187649 solutions

• First Factorial

For this challenge you will be determining the factorial for a given number. 171972 solutions

• Longest Word

For this challenge you will be determining the largest word in a string. 115670 solutions

• Letter Changes

For this challenge you will be manipulating characters in a string based off their positions in the alphabet. 118649 solutions

For this challenge you will be adding up all the numbers from 1 to a certain argument. 96121 solutions

• Letter Capitalize

For this challenge you will be capitalizing certain characters in a string. 79433 solutions

• Simple Symbols

For this challenge you will be determining whether or not certain characters are in correct positions. 67358 solutions

• Check Nums

For this challenge you will be comparing two numbers and determining which one is greater. 68104 solutions

• Time Convert

For this challenge you will be determining the difference in hours and minutes between two given times. 53403 solutions

• Alphabet Soup

For this challenge you will be sorting characters in a string. 48373 solutions

• AB Check

For this challenge you will determine if two characters are separated a specific way in the string. 18590 solutions

• Vowel Count

For this challenge you will be counting all the vowels in a string. 17125 solutions

• Word Count

For this challenge you will be determining how many words a sentence contains. 16205 solutions

• Ex Oh

For this challenge you will traverse a string and determine if there is an equal amount of certain characters. 15848 solutions

• Palindrome

For this challenge you will determine if a string is written the same way forward and backwards. 19019 solutions

• Arith Geo

For this challenge you will determine if numbers within an array follow an arithmetic or geometric sequence. 14597 solutions

For this challenge you will determine if numbers in an array can add up to a certain number in the array. 9728 solutions

• Letter Count I

For this challenge you will determine which word has the greatest number of repeated letters. 8965 solutions

• Second GreatLow

For this challenge you will determine the second lowest and greatest numbers in an array. 14572 solutions

• Division Stringified

For this challenge you will divide two numbers and return them in a certain format. 10715 solutions

• Counting Minutes I

For this challenge you will return the total number of minutes between two times. 6381 solutions

• Mean Mode

For this challenge you will determine if the mode equals the mean in an array. 8361 solutions

• Dash Insert

For this challenge you will be manipulating a string using dashes (-). 9554 solutions

• Swap Case

For this challenge you will be swapping the case of each character in the string. 8746 solutions

For this challenge you will traverse a string searching for all the numbers and then you will add them up. 8709 solutions

• Third Greatest

For this challenge you will determine the third largest string within an array. 8530 solutions

• Powers of Two

For this challenge you will be determining whether or not a number is a power of two. 9012 solutions

For this challenge you will be determining the additive persistence for a given number. 6602 solutions

• Multiplicative Persistence

For this challenge you will be determining the multiplicative persistence for a given number. 5125 solutions

• Off Line Minimum

For this challenge you will be creating a subset of an array. 6883 solutions

• Changing Sequence

For this challenge you will determine when an array changes sequences. 3661 solutions

• Overlapping Ranges

For this practice test you will determine the intersection between two sets. 3137 solutions

• Superincreasing

For this challenge you will determine if each number is greater than the sum of all previous elements in an array. 3198 solutions

• Hamming Distance

For this challenge you will determine the difference between two strings. 2419 solutions

• Rectangle Area

For this challenge you will determine the area of a rectangle. 2893 solutions

• Bitwise One

For this challenge you will perform a bitwise operation on two binary numbers. 2150 solutions

• Other Products

For this challenge you will return the product of a set of elements in an array. 2239 solutions

• Wave Sorting

For this challenge you will determine if numbers in an array can be sorted in a particular way. 1718 solutions

• Array Matching

For this challenge you will add elements from two arrays in a particular order. 2570 solutions

• Binary Reversal

For this challenge you will be reversing a binary string. 1834 solutions

• Longest Increasing Sequence

For this challenge you will compute the length of the longest increasing subsequence. 3028 solutions

• Even Pairs

For this challenge you will determine if a pair of even numbers exists somewhere in a string. 1502 solutions

• Next Palindrome

For this challenge you will be determining the next largest palindrome. 1442 solutions

• Largest Pair

For this challenge you will determine the largest double digit number. 1886 solutions

• Nonrepeating Character

For this challenge you will find the first non-repeating character in a string. 3475 solutions

• Two Sum

For this challenge you will determine if two elements can sum to some larger number. 3283 solutions

• Bitwise Two

For this challenge you will perform a bitwise operation on two binary numbers. 991 solutions

• Power Set Count

For this challenge you will determine the length of a power set. 1313 solutions

• Product Digits

For this challenge you will be determining the least amount of digits needed to produce a number. 1617 solutions

• Palindrome Creator

For this challenge you will be determining if you can create a palindrome from a list of numbers. 2288 solutions

• Basic Roman Numerals

For this challenge you will be converting a string of Roman numerals. 1134 solutions

• Food Distribution

For this challenge you will determine how to optimally distribute food to people. 1079 solutions

• Three Sum

For this challenge you will determine if three elements can sum to some larger number. 1318 solutions

• Correct Path

For this challenge you will be traversing a matrix searching for the correct path to take. 3869 solutions

• Scale Balancing

For this challenge you will be balancing a scale with weights on it. 5466 solutions

• Three Numbers

For this challenge you will be searching for a set of numbers in a string. 993 solutions

• Alphabet Searching

For this challenge you will determine if a set of characters exists in a string. 935 solutions

• Time Difference

For this challenge you will be searching for the smallest time difference. 826 solutions

• Triangle Row

For this challenge you will be adding up a whole row from Pascal's triangle. 502 solutions

• Vowel Square

For this challenge you will determine if a square of vowels exists in a matrix. 3426 solutions

• Closest Enemy

For this challenge you will search in an array for an enemy. 1787 solutions

• Closest Enemy II

For this challenge you will search in a matrix for an enemy. 3257 solutions

• Number Stream

For this challenge you will determine if a stream of digits occurs in a string. 1229 solutions

• Largest Four

For this challenge you will need to find the four largest elements in an array. 1439 solutions

• Distinct Characters

For this challenge you will determine if a string contains some number of distinct characters. 618 solutions

• Questions Marks

For this challenge you will be determining if a string follows a particular pattern. 9175 solutions

• Camel Case

For this challenge you will be converting a string into camel case format. 1860 solutions

• ASCII Conversion

For this challenge you will be replacing certain characters in a string. 510 solutions

• Simple Evens

For this challenge you will be checking whether a number is even. 692 solutions

• Snake Case

For this challenge you will be converting a string into snake case format. 996 solutions

• Find Intersection

For this challenge you will be manipulating an array. 2161 solutions

• Sum Multiplier

For this challenge you will determine if two numbers can be multiplied to some specific number. 1762 solutions

• String Merge

For this challenge you will be merging two different strings together. 745 solutions

• One Decremented

For this challenge you will be counting how many times a specific pattern occurs in a large number. 695 solutions

• Element Merger

For this challenge you will be combining all of the elements in an array into a single number. 729 solutions

• GCF

For this challenge you will determine the greatest common factor of two numbers. 658 solutions

• Serial Number

For this challenge you will be determining if a string produces a valid serial number. 1024 solutions

• String Periods

For this challenge you will need to find the smallest repeating substring. 1255 solutions

• Palindrome Swapper

For this challenge you will determine if a palindrome can be created in a string. 598 solutions

• Remove Brackets

For this challenge you will determine how to create evenly matched brackets. 1601 solutions

• Command Line

For this challenge you will be parsing a command line string and counting its characters. 332 solutions

• Star Rating

For this challenge you will be calculating how to display a 5 star rating. 1614 solutions

• Moving Median

For this challenge you will calculate the median in an array within a sliding window. 982 solutions

• Group Totals

For this challenge you will be adding values from key, value pairs. 1836 solutions

• String Changes

For this challenge you will manipulate a string based on two rules. 273 solutions

• FizzBuzz

For this challenge you will be solving the classic Fizz Buzz problem. 3037 solutions

• H Distance

For this challenge you will determine the difference between two strings. 426 solutions

• Different Cases

For this challenge you will be converting a string into camel case format. 322 solutions

• Equivalent Keypresses

For this challenge you will be manipulating an array. 449 solutions