58 total contributions since 2016

Solved

Encode Roman Numerals

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

5 months 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...

5 months 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 ...

5 months 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...

5 months 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...

5 months 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 ...

5 months 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...

5 months ago

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Interpolator

You have a two vectors, a and b. They are monotonic and the same length. Given a value, va, where va is between a(1) and a(end...

5 months 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, ...

10 months ago

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De-dupe

Remove all the redundant elements in a vector, but keep the first occurrence of each value in its original location. So if a =...

10 months ago

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Quote Doubler

Given a string s1, find all occurrences of the single quote character and replace them with two occurrences of the single quote ...

10 months ago

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Making change

Given an amount of currency, return a vector of this form: [100 50 20 10 5 2 1 0.5 0.25 0.1 0.05 0.01] Example: Input a = ...

10 months ago

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Balanced number

Given a positive integer find whether it is a balanced number. For a balanced number the sum of first half of digits is equal to...

10 months ago

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Replace NaNs with the number that appears to its left in the row.

Replace NaNs with the number that appears to its left in the row. If there are more than one consecutive NaNs, they should all ...

10 months ago

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Which doors are open?

There are n doors in an alley. Initially they are all shut. You have been tasked to go down the alley n times, and open/shut the...

10 months ago

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Counting Money

Add the numbers given in the cell array of strings. The strings represent amounts of money using this notation: $99,999.99. E...

10 months ago

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Binary numbers

Given a positive, scalar integer n, create a (2^n)-by-n double-precision matrix containing the binary numbers from 0 through 2^n...

10 months ago

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Pangrams!

A pangram, or holoalphabetic sentence, is a sentence using every letter of the alphabet at least once. Example: Input s ...

10 months ago

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Find the alphabetic word product

If the input string s is a word like 'hello', then the output word product p is a number based on the correspondence a=1, b=2, ....

10 months ago

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Cell joiner

You are given a cell array of strings and a string delimiter. You need to produce one string which is composed of each string fr...

10 months ago

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Find the longest sequence of 1's in a binary sequence.

Given a string such as s = '011110010000000100010111' find the length of the longest string of consecutive 1's. In this examp...

10 months ago

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Remove all the consonants

Remove all the consonants in the given phrase. Example: Input s1 = 'Jack and Jill went up the hill'; Output s2 is 'a ...

10 months ago

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Weighted average

Given two lists of numbers, determine the weighted average. Example [1 2 3] and [10 15 20] should result in 33.333...

10 months ago

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Nearest Numbers

Given a row vector of numbers, find the indices of the two nearest numbers. Examples: [index1 index2] = nearestNumbers([2 5 3...

11 months ago

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Target sorting

Sort the given list of numbers |a| according to how far away each element is from the target value |t|. The result should return...

11 months ago

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Return the largest number that is adjacent to a zero

This example comes from Steve Eddins' blog: <http://blogs.mathworks.com/steve/2009/05/27/learning-lessons-from-a-one-liner/ Lear...

11 months 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 ...

11 months ago

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Bullseye Matrix

Given n (always odd), return output a that has concentric rings of the numbers 1 through (n+1)/2 around the center point. Exampl...

11 months ago

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Which values occur exactly three times?

Return a list of all values (sorted smallest to largest) that appear exactly three times in the input vector x. So if x = [1 2...

11 months ago

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Sort a list of complex numbers based on far they are from the origin.

Given a list of complex numbers z, return a list zSorted such that the numbers that are farthest from the origin (0+0i) appear f...

11 months ago