Solved

Triangle Numbers Below N
This is an offshoot of <http://www.mathworks.com/matlabcentral/cody/problems/5-triangle-numbers Cody Problem 5: Triangle Numbers...

13 years ago

Solved

Make a random, non-repeating vector.
This is a basic MATLAB operation. It is for instructional purposes. --- If you want to get a random permutation of integer...

13 years ago

Solved

Flip the main diagonal of a matrix
Given a n x n matrix, M, flip its main diagonal. Example: >> M=magic(5); >> flipDiagonal(M) 9 24 1 ...

13 years ago

Solved

Convert a vector into a number
This is a sub problem related to this problem: <http://www.mathworks.com/matlabcentral/cody/problems/621-cryptomath-addition>...

13 years ago

Solved

Remove the air bubbles
Given a matrix a, return a matrix b in which all the zeros have "bubbled" to the top. That is, any zeros in a given column shoul...

13 years ago

Solved

Number of 1s in a binary string
Find the number of 1s in the given binary string. Example. If the input string is '1100101', the output is 4. If the input stri...

13 years ago

Solved

First N Perfect Squares
*Description* Return the first N perfect squares *Example* input = 4; output = [ 1 4 9 16 ];

13 years ago

Solved

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

13 years 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...

13 years ago

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So many choices
For inputs _n_ and _k_ (in that order), output the number of ways that k objects can be chosen from amongst n distinct objects. ...

13 years ago

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...

13 years ago

Solved

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 ...

13 years 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...

13 years ago

Solved

Check to see if a Sudoku Puzzle is Solved
*Description:* Your task, should you choose to accept it, is to make a function that checks to see if a 9x9 matrix of integer...

13 years ago

Solved

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

13 years ago

Solved

Implement simple rotation cypher
If given a letter from the set: [abc...xyz] and a shift, implement a shift cypher. Example: 'abc' with a shi...

13 years ago

Solved

Scoring for oriented dominoes
Given a list of ordered pairs, and the order they should be placed in a line, find the sum of the absolute values of the differe...

13 years ago

Solved

Find a subset that divides the vector into equal halves
Given a vector x, return the indices to elements that will sum to exactly half of the sum of all elements. Example: Inpu...

13 years ago

Solved

Stuff the Board
You have a stack of tiles to put onto an array-like playing board. Each tile has a number (always an integer), and the board var...

13 years ago

Solved

Vectorize the digits of an Integer
Create a vector of length N for an integer of N digits. x=123045; x_vec=[1 2 3 0 4 5]; I happened upon a trick to do ...

13 years ago

Solved

Is A the inverse of B?
Given a matrix A and a matrix B, is A the inverse of B? >>A=[2,4;3,5]; >>B=[-2.5,2;1.5,-1]; >>isInverse...

13 years ago

Solved

Set the array elements whose value is 13 to 0
Input A either an array or a vector (which can be empty) Output B will be the same size as A . All elements of A equal to 13...

13 years 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 ...

13 years ago

Solved

Increment a number, given its digits
Take as input an array of digits (e.g. x = [1 2 3]) and output an array of digits that is that number "incremented" properly, (i...

13 years 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 ...

13 years ago

Solved

Back to basics 22 - Rotate a matrix
Covering some basic topics I haven't seen elsewhere on Cody. Rotate the input matrix 90 degrees counterclockwise (e.g. [1 2; ...

13 years ago

Solved

Number of 1s in the Binary Representation of a Number
*Description* Return the number of 1s in the (unsigned integer) binary representation of a number. This function should be ab...

13 years 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...

13 years ago

Solved

Given an unsigned integer x, find the largest y by rearranging the bits in x
Given an unsigned integer x, find the largest y by rearranging the bits in x. Example: Input x = 10 Output y is 12 ...

13 years ago

Solved

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

13 years ago