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# ben niu

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84 total contributions since 2015

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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...

meer dan 4 jaar ago

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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...

meer dan 4 jaar 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...

meer dan 4 jaar ago

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Is this triangle right-angled?
Given three positive numbers a, b, c, where c is the largest number, return *true* if the triangle with sides a, b and c is righ...

meer dan 4 jaar ago

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Back to basics 6 - Column Vector
Covering some basic topics I haven't seen elsewhere on Cody. Given an input vector, output true or false whether it is a colu...

meer dan 4 jaar ago

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Factorize THIS, buddy
List the prime factors for the input number, in decreasing order. List each factor only once, even if the factorization includes...

meer dan 4 jaar ago

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Solve the Sudoku Row
*Description* A simple yet tedious task occurs near the end of most Sudoku-solving algorithms, computerized or manual. The ta...

meer dan 4 jaar ago

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Find the sum of the elements in the "second" diagonal
Find the sum of the elements in the diagonal that starts at the top-right corner and ends at the bottom-left corner.

meer dan 4 jaar ago

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Sum of diagonal of a square matrix
If x = [1 2 4; 3 4 5; 5 6 7] then y should be the sum of the diagonals of the matrix y = 1 + 4 + 7 = 12

meer dan 4 jaar ago

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Multielement indexing of a row array
The row array birthRateChina stores the China birth rate (per 1000 people) for years 2000 to 2012. Write a statement that create...

meer dan 4 jaar ago

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Tell me the slope
Tell me the slope, given a vector with horizontal run first and vertical rise next. Example input: x = [10 2];

meer dan 4 jaar ago

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

meer dan 4 jaar ago

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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 ...

meer dan 4 jaar 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...

meer dan 4 jaar 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 = ...

meer dan 4 jaar ago

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Reverse Run-Length Encoder
Given a "counting sequence" vector x, construct the original sequence y. A counting sequence is formed by "counting" the entrie...

meer dan 4 jaar ago

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Project Euler: Problem 1, Multiples of 3 and 5
If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9. The sum of these multiples is 23...

meer dan 4 jaar 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...

meer dan 4 jaar ago

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Make one big string out of two smaller strings
If you have two small strings, like 'a' and 'b', return them put together like 'ab'. 'a' and 'b' => 'ab' For extra ...

meer dan 4 jaar 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, ...

meer dan 4 jaar 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 =...

meer dan 4 jaar ago

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Arrange Vector in descending order
If x=[0,3,4,2,1] then y=[4,3,2,1,0]

meer dan 4 jaar 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...

meer dan 4 jaar 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 ...

meer dan 4 jaar ago

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Sorted highest to lowest?
Return 1 if the input is sorted from highest to lowest, 0 if not. Example: 1:7 -> 0 [7 5 2] -> 1

meer dan 4 jaar ago

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inner product of two vectors
inner product of two vectors

meer dan 4 jaar 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 ...

meer dan 4 jaar ago

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Is my wife right? Now with even more wrong husband
Again, as in "Is my wife right?" ( <http://www.mathworks.com/matlabcentral/cody/problems/149-is-my-wife-right> ), answer 'yes' r...

meer dan 4 jaar ago

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Lightning strike distance: Writing a function
Write a function named LightningDistance that outputs "distance" given input "seconds". Seconds is the time from seeing lightnin...

meer dan 4 jaar 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 ...

meer dan 4 jaar ago