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Course Material

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• Practice Challenges
• First Reverse

For this challenge you will be reversing a string. 169721 solutions

• First Factorial

For this challenge you will be determining the factorial for a given number. 157206 solutions

• Longest Word

For this challenge you will be determining the largest word in a string. 107523 solutions

• Letter Changes

For this challenge you will be manipulating characters in a string based off their positions in the alphabet. 109051 solutions

For this challenge you will be adding up all the numbers from 1 to a certain argument. 88459 solutions

• Letter Capitalize

For this challenge you will be capitalizing certain characters in a string. 75587 solutions

• Simple Symbols

For this challenge you will be determining whether or not certain characters are in correct positions. 64320 solutions

• Check Nums

For this challenge you will be comparing two numbers and determining which one is greater. 64683 solutions

• Time Convert

For this challenge you will be determining the difference in hours and minutes between two given times. 49949 solutions

• Alphabet Soup

For this challenge you will be sorting characters in a string. 44795 solutions

• AB Check

For this challenge you will determine if two characters are separated a specific way in the string. 18198 solutions

• Vowel Count

For this challenge you will be counting all the vowels in a string. 16644 solutions

• Word Count

For this challenge you will be determining how many words a sentence contains. 15574 solutions

• Ex Oh

For this challenge you will traverse a string and determine if there is an equal amount of certain characters. 15341 solutions

• Palindrome

For this challenge you will determine if a string is written the same way forward and backwards. 18124 solutions

• Arith Geo

For this challenge you will determine if numbers within an array follow an arithmetic or geometric sequence. 14338 solutions

• Array Addition I

For this challenge you will determine if numbers in an array can add up to a certain number in the array. 9419 solutions

• Letter Count I

For this challenge you will determine which word has the greatest number of repeated letters. 8547 solutions

• Second GreatLow

For this challenge you will determine the second lowest and greatest numbers in an array. 14283 solutions

• Division Stringified

For this challenge you will divide two numbers and return them in a certain format. 10505 solutions

• Counting Minutes I

For this challenge you will return the total number of minutes between two times. 6229 solutions

• Mean Mode

For this challenge you will determine if the mode equals the mean in an array. 8206 solutions

• Dash Insert

For this challenge you will be manipulating a string using dashes (-). 9227 solutions

• Swap Case

For this challenge you will be swapping the case of each character in the string. 8578 solutions

For this challenge you will traverse a string searching for all the numbers and then you will add them up. 8538 solutions

• Third Greatest

For this challenge you will determine the third largest string within an array. 8215 solutions

• Powers of Two

For this challenge you will be determining whether or not a number is a power of two. 8847 solutions

For this challenge you will be determining the additive persistence for a given number. 6437 solutions

• Multiplicative Persistence

For this challenge you will be determining the multiplicative persistence for a given number. 4980 solutions

• Off Line Minimum

For this challenge you will be creating a subset of an array. 6678 solutions

• Changing Sequence

For this challenge you will determine when an array changes sequences. 3313 solutions

• Overlapping Ranges

For this practice test you will determine the intersection between two sets. 2995 solutions

• Superincreasing

For this challenge you will determine if each number is greater than the sum of all previous elements in an array. 3007 solutions

• Hamming Distance

For this challenge you will determine the difference between two strings. 2110 solutions

• Rectangle Area

For this challenge you will determine the area of a rectangle. 2533 solutions

• Bitwise One

For this challenge you will perform a bitwise operation on two binary numbers. 2034 solutions

• Other Products

For this challenge you will return the product of a set of elements in an array. 2149 solutions

• Wave Sorting

For this challenge you will determine if numbers in an array can be sorted in a particular way. 1573 solutions

• Array Matching

For this challenge you will add elements from two arrays in a particular order. 1950 solutions

• Binary Reversal

For this challenge you will be reversing a binary string. 1690 solutions

• Longest Increasing Sequence

For this challenge you will compute the length of the longest increasing subsequence. 2022 solutions

• Even Pairs

For this challenge you will determine if a pair of even numbers exists somewhere in a string. 1419 solutions

• Next Palindrome

For this challenge you will be determining the next largest palindrome. 1373 solutions

• Largest Pair

For this challenge you will determine the largest double digit number. 1625 solutions

• Nonrepeating Character

For this challenge you will find the first non-repeating character in a string. 2240 solutions

• Two Sum

For this challenge you will determine if two elements can sum to some larger number. 2968 solutions

• Bitwise Two

For this challenge you will perform a bitwise operation on two binary numbers. 917 solutions

• Power Set Count

For this challenge you will determine the length of a power set. 1248 solutions

• Product Digits

For this challenge you will be determining the least amount of digits needed to produce a number. 1548 solutions

• Palindrome Creator

For this challenge you will be determining if you can create a palindrome from a list of numbers. 1714 solutions

• Basic Roman Numerals

For this challenge you will be converting a string of Roman numerals. 971 solutions

• Food Distribution

For this challenge you will determine how to optimally distribute food to people. 947 solutions

• Three Sum

For this challenge you will determine if three elements can sum to some larger number. 1164 solutions

• Correct Path

For this challenge you will be traversing a matrix searching for the correct path to take. 3108 solutions

• Scale Balancing

For this challenge you will be balancing a scale with weights on it. 4628 solutions

• Three Numbers

For this challenge you will be searching for a set of numbers in a string. 933 solutions

• Alphabet Searching

For this challenge you will determine if a set of characters exists in a string. 866 solutions

• Time Difference

For this challenge you will be searching for the smallest time difference. 617 solutions

• Triangle Row

For this challenge you will be adding up a whole row from Pascal's triangle. 476 solutions

• Vowel Square

For this challenge you will determine if a square of vowels exists in a matrix. 2839 solutions

• Closest Enemy

For this challenge you will search in an array for an enemy. 1013 solutions

• Closest Enemy II

For this challenge you will search in a matrix for an enemy. 2826 solutions

• Number Stream

For this challenge you will determine if a stream of digits occurs in a string. 597 solutions

• Largest Four

For this challenge you will need to find the four largest elements in an array. 1007 solutions

• Distinct Characters

For this challenge you will determine if a string contains some number of distinct characters. 549 solutions

• Questions Marks

For this challenge you will be determining if a string follows a particular pattern. 7388 solutions

• Camel Case

For this challenge you will be converting a string into camel case format. 722 solutions

• ASCII Conversion

For this challenge you will be replacing certain characters in a string. 450 solutions

• Simple Evens

For this challenge you will be checking whether a number is even. 596 solutions

• Snake Case

For this challenge you will be converting a string into snake case format. 716 solutions

• Sum Multiplier

For this challenge you will determine if two numbers can be multiplied to some specific number. 871 solutions

• String Merge

For this challenge you will be merging two different strings together. 639 solutions

• One Decremented

For this challenge you will be counting how many times a specific pattern occurs in a large number. 610 solutions

• Element Merger

For this challenge you will be combining all of the elements in an array into a single number. 628 solutions

• GCF

For this challenge you will determine the greatest common factor of two numbers. 609 solutions

• Serial Number

For this challenge you will be determining if a string produces a valid serial number. 768 solutions

• String Periods

For this challenge you will need to find the smallest repeating substring. 759 solutions

• Palindrome Swapper

For this challenge you will determine if a palindrome can be created in a string. 495 solutions

• Remove Brackets

For this challenge you will determine how to create evenly matched brackets. 890 solutions

• Command Line

For this challenge you will be parsing a command line string and counting its characters. 308 solutions

• Star Rating

For this challenge you will be calculating how to display a 5 star rating. 1150 solutions

• Moving Median

For this challenge you will calculate the median in an array within a sliding window. 595 solutions

• Group Totals

For this challenge you will be adding values from key, value pairs. 1077 solutions

• String Changes

For this challenge you will manipulate a string based on two rules. 219 solutions

• FizzBuzz

For this challenge you will be solving the classic Fizz Buzz problem. 2172 solutions

• H Distance

For this challenge you will determine the difference between two strings. 262 solutions

• Different Cases

For this challenge you will be converting a string into camel case format. 263 solutions