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Course Material

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• Practice Challenges
• First Reverse

For this challenge you will be reversing a string. 239571 solutions

• First Factorial

For this challenge you will be determining the factorial for a given number. 215004 solutions

• Longest Word

For this challenge you will be determining the largest word in a string. 155401 solutions

• Letter Changes

For this challenge you will be manipulating characters in a string based off their positions in the alphabet. 131105 solutions

For this challenge you will be adding up all the numbers from 1 to a certain argument. 109720 solutions

• Letter Capitalize

For this challenge you will be capitalizing certain characters in a string. 92084 solutions

• Simple Symbols

For this challenge you will be determining whether or not certain characters are in correct positions. 71151 solutions

• Check Nums

For this challenge you will be comparing two numbers and determining which one is greater. 75567 solutions

• Time Convert

For this challenge you will be determining the difference in hours and minutes between two given times. 68453 solutions

• Alphabet Soup

For this challenge you will be sorting characters in a string. 56217 solutions

• AB Check

For this challenge you will determine if two characters are separated a specific way in the string. 24817 solutions

• Vowel Count

For this challenge you will be counting all the vowels in a string. 24787 solutions

• Word Count

For this challenge you will be determining how many words a sentence contains. 23901 solutions

• Ex Oh

For this challenge you will traverse a string and determine if there is an equal amount of certain characters. 20442 solutions

• Palindrome

For this challenge you will determine if a string is written the same way forward and backwards. 32463 solutions

• Arith Geo

For this challenge you will determine if numbers within an array follow an arithmetic or geometric sequence. 18836 solutions

For this challenge you will determine if numbers in an array can add up to a certain number in the array. 15480 solutions

• Letter Count I

For this challenge you will determine which word has the greatest number of repeated letters. 11528 solutions

• Second GreatLow

For this challenge you will determine the second lowest and greatest numbers in an array. 19158 solutions

• Division Stringified

For this challenge you will divide two numbers and return them in a certain format. 12322 solutions

• Counting Minutes I

For this challenge you will return the total number of minutes between two times. 8546 solutions

• Mean Mode

For this challenge you will determine if the mode equals the mean in an array. 10854 solutions

• Dash Insert

For this challenge you will be manipulating a string using dashes (-). 12484 solutions

• Swap Case

For this challenge you will be swapping the case of each character in the string. 12003 solutions

For this challenge you will traverse a string searching for all the numbers and then you will add them up. 10685 solutions

• Third Greatest

For this challenge you will determine the third largest string within an array. 13649 solutions

• Powers of Two

For this challenge you will be determining whether or not a number is a power of two. 15361 solutions

For this challenge you will be determining the additive persistence for a given number. 8453 solutions

• Multiplicative Persistence

For this challenge you will be determining the multiplicative persistence for a given number. 7393 solutions

• Off Line Minimum

For this challenge you will be creating a subset of an array. 8447 solutions

• Changing Sequence

For this challenge you will determine when an array changes sequences. 6247 solutions

• Overlapping Ranges

For this practice test you will determine the intersection between two sets. 5828 solutions

• Superincreasing

For this challenge you will determine if each number is greater than the sum of all previous elements in an array. 4816 solutions

• Hamming Distance

For this challenge you will determine the difference between two strings. 4222 solutions

• Rectangle Area

For this challenge you will determine the area of a rectangle. 5484 solutions

• Bitwise One

For this challenge you will perform a bitwise operation on two binary numbers. 3750 solutions

• Other Products

For this challenge you will return the product of a set of elements in an array. 3538 solutions

• Wave Sorting

For this challenge you will determine if numbers in an array can be sorted in a particular way. 5758 solutions

• Array Matching

For this challenge you will add elements from two arrays in a particular order. 6341 solutions

• Binary Reversal

For this challenge you will be reversing a binary string. 6856 solutions

• Next Palindrome

For this challenge you will be determining the next largest palindrome. 3025 solutions

• Largest Pair

For this challenge you will determine the largest double digit number. 4278 solutions

• Nonrepeating Character

For this challenge you will find the first non-repeating character in a string. 16416 solutions

• Two Sum

For this challenge you will determine if two elements can sum to some larger number. 9153 solutions

• Bitwise Two

For this challenge you will perform a bitwise operation on two binary numbers. 1955 solutions

• Power Set Count

For this challenge you will determine the length of a power set. 2413 solutions

• Product Digits

For this challenge you will be determining the least amount of digits needed to produce a number. 3406 solutions

• Palindrome Creator

For this challenge you will be determining if you can create a palindrome from a list of numbers. 9730 solutions

• Basic Roman Numerals

For this challenge you will be converting a string of Roman numerals. 3342 solutions

• Three Sum

For this challenge you will determine if three elements can sum to some larger number. 4495 solutions

• Correct Path

For this challenge you will be traversing a matrix searching for the correct path to take. 4958 solutions

• Scale Balancing

For this challenge you will be balancing a scale with weights on it. 6672 solutions

• Three Numbers

For this challenge you will be searching for a set of numbers in a string. 2058 solutions

• Alphabet Searching

For this challenge you will determine if a set of characters exists in a string. 1945 solutions

• Time Difference

For this challenge you will be searching for the smallest time difference. 3706 solutions

• Triangle Row

For this challenge you will be adding up a whole row from Pascal's triangle. 1195 solutions

• Vowel Square

For this challenge you will determine if a square of vowels exists in a matrix. 4114 solutions

• Closest Enemy

For this challenge you will search in an array for an enemy. 6411 solutions

• Closest Enemy II

For this challenge you will search in a matrix for an enemy. 4900 solutions

• Number Stream

For this challenge you will determine if a stream of digits occurs in a string. 7063 solutions

• Largest Four

For this challenge you will need to find the four largest elements in an array. 14611 solutions

• Distinct Characters

For this challenge you will determine if a string contains some number of distinct characters. 1906 solutions

• Questions Marks

For this challenge you will be determining if a string follows a particular pattern. 28353 solutions

• Camel Case

For this challenge you will be converting a string into camel case format. 12116 solutions

• ASCII Conversion

For this challenge you will be replacing certain characters in a string. 2560 solutions

• Simple Evens

For this challenge you will be checking whether a number is even. 1996 solutions

• Snake Case

For this challenge you will be converting a string into snake case format. 4023 solutions

• Find Intersection

For this challenge you will be manipulating an array. 39605 solutions

• Sum Multiplier

For this challenge you will determine if two numbers can be multiplied to some specific number. 13257 solutions

• String Merge

For this challenge you will be merging two different strings together. 1857 solutions

• One Decremented

For this challenge you will be counting how many times a specific pattern occurs in a large number. 1823 solutions

• Element Merger

For this challenge you will be combining all of the elements in an array into a single number. 1803 solutions

• GCF

For this challenge you will determine the greatest common factor of two numbers. 1800 solutions

• Serial Number

For this challenge you will be determining if a string produces a valid serial number. 3543 solutions

• String Periods

For this challenge you will need to find the smallest repeating substring. 7875 solutions

• Palindrome Swapper

For this challenge you will determine if a palindrome can be created in a string. 1701 solutions

• Remove Brackets

For this challenge you will determine how to create evenly matched brackets. 8844 solutions

• Command Line

For this challenge you will be parsing a command line string and counting its characters. 1344 solutions

• Star Rating

For this challenge you will be calculating how to display a 5 star rating. 9154 solutions

• Moving Median

For this challenge you will calculate the median in an array within a sliding window. 6389 solutions

• Group Totals

For this challenge you will be adding values from key, value pairs. 9294 solutions

• String Changes

For this challenge you will manipulate a string based on two rules. 1817 solutions

• FizzBuzz

For this challenge you will be solving the classic Fizz Buzz problem. 10277 solutions

• H Distance

For this challenge you will determine the difference between two strings. 2109 solutions

• Different Cases

For this challenge you will be converting a string into camel case format. 1605 solutions

• Equivalent Keypresses

For this challenge you will be manipulating an array. 2601 solutions

A premium challenge for the Codeland conference. 19265 solutions

• Consonant Count

For this challenge you will be counting all the consonant in a string. 836 solutions

• Happy Numbers

For this challenge you will be determining whether or not a number is Happy. 680 solutions

• Number Reverse

For this challenge you will be reversing a string. 1147 solutions