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Return the 3n+1 sequence for n

A Collatz sequence is the sequence where, for a given number n, the next number in the sequence is either n/2 if the number is e...

1 year ago

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Find the numeric mean of the prime numbers in a matrix.

There will always be at least one prime in the matrix. Example: Input in = [ 8 3 5 9 ] Output out is 4...

1 year ago

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Fibonacci sequence

Calculate the nth Fibonacci number. Given n, return f where f = fib(n) and f(1) = 1, f(2) = 1, f(3) = 2, ... Examples: Inpu...

1 year ago

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Duplicates

Write a function that accepts a cell array of strings and returns another cell array of strings *with only the duplicates* retai...

1 year ago

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Tic Tac Toe FTW

Given a tic tac toe board: * 1 represents X * 0 represents empty. * -1 represents O It is X's move. If there is an imme...

1 year ago

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Pattern matching

Given a matrix, m-by-n, find all the rows that have the same "increase, decrease, or stay same" pattern going across the columns...

1 year ago

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Encode Roman Numerals

Create a function taking a non-negative integer as its parameter and returning a string containing the Roman Numeral representat...

1 year ago

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The Goldbach Conjecture

The <http://en.wikipedia.org/wiki/Goldbach's_conjecture Goldbach conjecture> asserts that every even integer greater than 2 can ...

1 year ago

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Elapsed Time

Given two date strings d1 and d2 of the form yyyy/mm/dd HH:MM:SS (assume hours HH is in 24 hour mode), determine how much time, ...

1 year ago

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Counting in Finnish

Sort a vector of single digit whole numbers alphabetically by their name, in Finnish. See the Wikipedia page for <http://en.wik...

1 year ago

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Find state names that end with the letter A

Given a list of US states, remove all the states that end with the letter A. Example: Input s1 = 'Alabama Montana Nebras...

1 year ago

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The Goldbach Conjecture, Part 2

The <http://en.wikipedia.org/wiki/Goldbach's_conjecture Goldbach conjecture> asserts that every even integer greater than 2 can ...

1 year ago

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Find the two-word state names

Given a list of states, remove all the states that have two-word names. If s1 = 'Alabama Montana North Carolina Vermont N...

1 year ago

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Kaprekar Steps

6174 is the <http://en.wikipedia.org/wiki/6174_%28number%29 Kaprekar constant>. All natural numbers less than 10,000 (except som...

1 year ago

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Read a column of numbers and interpolate missing data

Given an input cell array of strings s, pick out the second column and turn it into a row vector of data. Missing data will be i...

1 year ago

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Alphabetize by last name

Given a list of names in a cell array, sort the list by the last name. So if list = {'Barney Google','Snuffy Smith','Dagwood ...

1 year ago

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Mandelbrot Numbers

The <http://en.wikipedia.org/wiki/Mandelbrot_set Mandelbrot Set> is built around a simple iterative equation. z(1) = c z...

1 year ago

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Connect Four Win Checker

<http://en.wikipedia.org/wiki/Connect_Four Connect Four> is a game where you try to get four pieces in a row. For this problem, ...

1 year ago

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Find common elements in matrix rows

Given a matrix, find all elements that exist in every row. For example, given A = 1 2 3 5 9 2 5 9 3 2 5 9 ...

1 year ago

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Find the two most distant points

Given a collection of points, return the indices of the rows that contain the two points most distant from one another. The inpu...

1 year ago

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Determine if input is odd

Given the input n, return true if n is odd or false if n is even.

1 year ago

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Word Counting and Indexing

You are given a list of strings, each being a list of words divided by spaces. Break the strings into words, then return a maste...

1 year ago

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Prime factor digits

Consider the following number system. Calculate the prime factorization for each number n, then represent the prime factors in a...

1 year ago

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Get the area codes from a list of phone numbers

Given a string of text with phone numbers in it, return a unique'd cell array of strings that are the area codes. s = '508-647...

1 year ago

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It dseon't mettar waht oedrr the lrettes in a wrod are.

An internet meme from 2003 (read more here) asserted that readers are relatively insensitive to letter order in words, so long a...

1 year ago

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Remove the polynomials that have positive real elements of their roots.

The characteristic equation for a dynamic system is a polynomial whose roots indicate its behavior. If any of the roots of the p...

1 year ago

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Find state names that start with the letter N

Given a list of US states, remove all the states that start with the letter N. If s1 = 'Alabama Montana Nebraska Vermont Ne...

1 year ago

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Find the peak 3n+1 sequence value

A Collatz sequence is the sequence where, for a given number n, the next number in the sequence is either n/2 if the number is e...

1 year ago

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Find relatively common elements in matrix rows

You want to find all elements that exist in greater than 50% of the rows in the matrix. For example, given A = 1 2 3 5 ...

1 year ago

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QWERTY coordinates

Given a lowercase letter or a digit as input, return the row where that letter appears on a standard U.S. QWERTY keyboard and it...

1 year ago