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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

• Array Addition I

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

• Codeland Username Validation

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