Solved

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

Solved

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

Solved

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

Solved

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

Solved

Scrabble Scores

Given a word, determine its score in <http://en.wikipedia.org/wiki/Scrabble Scrabble>. The input string will always be provi...

1 year ago

Solved

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

Solved

Function Iterator

Given a handle fh to a function which takes a scalar input and returns a scalar output and an integer n >= 1, return a handle f...

1 year ago

Solved

Test for balanced parentheses

Given the input inStr, give the boolean output out indicating whether all the parentheses are balanced. Examples: * If ...

1 year ago

Solved

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

Solved

Indexed Probability Table

This question was inspired by a Stack Overflow question forwarded to me by Matt Simoneau. Given a vector x, make an indexed pro...

1 year ago

Solved

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

Solved

Summing Digits within Text

Given a string with text and digits, add all the numbers together. Examples: Input str = '4 and 20 blackbirds baked in a...

1 year ago

Solved

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

Solved

Maximum running product for a string of numbers

Given a string s representing a list of numbers, find the five consecutive numbers that multiply to form the largest number. Spe...

1 year ago

Solved

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

Solved

What is the next step in Conway's Life?

Given a matrix A that represents the state of <http://en.wikipedia.org/wiki/Conway's_Game_of_Life Conway's game of Life> at one ...

1 year ago

Solved

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

Solved

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

Solved

QWERTY coordinates

Given a lowercase letter or a digit as input, return the row where that letter appears on a <http://en.wikipedia.org/wiki/Keyboa...

1 year ago

Solved

Sums with Excluded Digits

Add all the integers from 1 to n in which the digit m does not appear. m will always be a single digit integer from 0 to 9. no...

1 year ago

Solved

Extract leading non-zero digit

<http://en.wikipedia.org/wiki/Benford%27s_law Benford's Law> states that the distribution of leading digits is not random. This...

1 year ago

Solved

Make a Palindrome Number

Some numbers like 323 are palindromes. Other numbers like 124 are not. But look what happens when we add that number to a revers...

1 year ago

Solved

Trimming Spaces

Given a string, remove all leading and trailing spaces (where space is defined as ASCII 32). Input a = ' singular value deco...

1 year ago

Solved

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 =...

1 year ago

Solved

Subset Sum

Given a vector v of integers and an integer n, return the the indices of v (as a row vector in ascending order) that sum to n. I...

1 year ago

Solved

Reverse Run-Length Encoder

Given a "counting sequence" vector x, construct the original sequence y. A counting sequence is formed by "counting" the entrie...

1 year ago

Solved

Return a list sorted by number of occurrences

Given a vector x, return a vector y of the unique values in x sorted by the number of occurrences in x. Ties are resolved by a ...

1 year ago

Solved

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 = ...

1 year ago

Solved

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

Solved

Quote Doubler

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

1 year ago