Given non-negative integers m and n, generate all size m combinations of the integers from 0 (zero) to n-1 in sorted order (each combination is sorted and the entire table is sorted).
-Example: -3 comb 5 is:
+Given non-negative integers m and n, generate all size m combinations of the integers from 0 (zero) to n-1 in sorted order (each combination is sorted and the entire table is sorted). +Example: +3 comb 5 is:0 1 2 0 1 3 diff --git a/curriculum/challenges/english/08-coding-interview-prep/rosetta-code/comma-quibbling.english.md b/curriculum/challenges/english/08-coding-interview-prep/rosetta-code/comma-quibbling.english.md index 294dd5474c..48effb8573 100644 --- a/curriculum/challenges/english/08-coding-interview-prep/rosetta-code/comma-quibbling.english.md +++ b/curriculum/challenges/english/08-coding-interview-prep/rosetta-code/comma-quibbling.english.md @@ -6,18 +6,22 @@ challengeType: 5 ## Description- ## Instructions diff --git a/curriculum/challenges/english/08-coding-interview-prep/rosetta-code/compare-a-list-of-strings.english.md b/curriculum/challenges/english/08-coding-interview-prep/rosetta-code/compare-a-list-of-strings.english.md index 0f3d403f4e..50883afb3d 100644 --- a/curriculum/challenges/english/08-coding-interview-prep/rosetta-code/compare-a-list-of-strings.english.md +++ b/curriculum/challenges/english/08-coding-interview-prep/rosetta-code/compare-a-list-of-strings.english.md @@ -6,8 +6,11 @@ challengeType: 5 ## DescriptionComma quibbling is a task originally set by Eric Lippert in his blog.
-Task:Write a function to generate a string output which is the concatenation of input words from a list/sequence where:
-An input of no words produces the output string of just the two brace characters "{}". -An input of just one word, e.g. ["ABC"], produces the output string of the word inside the two braces, e.g. "{ABC}". -An input of two words, e.g. ["ABC", "DEF"], produces the output string of the two words inside the two braces with the words separated by the string " and ", e.g. "{ABC and DEF}". -An input of three or more words, e.g. ["ABC", "DEF", "G", "H"], produces the output string of all but the last word separated by ", " with the last word separated by " and " and all within braces; e.g. "{ABC, DEF, G and H}". -Test your function with the following series of inputs showing your output here on this page:
-[] # (No input words). -["ABC"] -["ABC", "DEF"] -["ABC", "DEF", "G", "H"] -Note: Assume words are non-empty strings of uppercase characters for this task.
+Comma quibbling is a task originally set by Eric Lippert in his blog. +Write a function to generate a string output which is the concatenation of input words from a list/sequence where: ++
+Test your function with the following series of inputs showing your output here on this page: +- An input of no words produces the output string of just the two brace characters "{}".
+- An input of just one word, e.g. ["ABC"], produces the output string of the word inside the two braces, e.g. "{ABC}".
+- An input of two words, e.g. ["ABC", "DEF"], produces the output string of the two words inside the two braces with the words separated by the string " and ", e.g. "{ABC and DEF}".
+- An input of three or more words, e.g. ["ABC", "DEF", "G", "H"], produces the output string of all but the last word separated by ", " with the last word separated by " and " and all within braces; e.g. "{ABC, DEF, G and H}".
++
+Note: Assume words are non-empty strings of uppercase characters for this task.- [] # (No input words).
+- ["ABC"]
+- ["ABC", "DEF"]
+- ["ABC", "DEF", "G", "H"]
+- ## Instructions diff --git a/curriculum/challenges/english/08-coding-interview-prep/rosetta-code/convert-seconds-to-compound-duration.english.md b/curriculum/challenges/english/08-coding-interview-prep/rosetta-code/convert-seconds-to-compound-duration.english.md index 7fc63db3ac..bd6824155f 100644 --- a/curriculum/challenges/english/08-coding-interview-prep/rosetta-code/convert-seconds-to-compound-duration.english.md +++ b/curriculum/challenges/english/08-coding-interview-prep/rosetta-code/convert-seconds-to-compound-duration.english.md @@ -6,69 +6,82 @@ challengeType: 5 ## DescriptionGiven a list of arbitrarily many strings, implement a function for each of the following conditions:
test if they are all lexically equal - test if every string is lexically less than the one after it (i.e. whether the list is in strict ascending order) +Given a list of arbitrarily many strings, implement a function for each of the following conditions: ++
- test if they are all lexically equal
+- test if every string is lexically less than the one after it (i.e. whether the list is in strict ascending order)
+-Task: - ## Instructions diff --git a/curriculum/challenges/english/08-coding-interview-prep/rosetta-code/count-occurrences-of-a-substring.english.md b/curriculum/challenges/english/08-coding-interview-prep/rosetta-code/count-occurrences-of-a-substring.english.md index 3ecd2715d5..a25ed5e53a 100644 --- a/curriculum/challenges/english/08-coding-interview-prep/rosetta-code/count-occurrences-of-a-substring.english.md +++ b/curriculum/challenges/english/08-coding-interview-prep/rosetta-code/count-occurrences-of-a-substring.english.md @@ -6,12 +6,15 @@ challengeType: 5 ## DescriptionImplement a function which:
-takes a positive integer representing a duration in seconds as input (e.g.,100), and -returns a string which shows the same duration decomposed into weeks, days, hours, minutes, and seconds as detailed below (e.g.,1 min, 40 sec). -Demonstrate that it passes the following three test-cases:
Test Cases
+Implement a function which: ++
+Demonstrate that it passes the following three test-cases: +- takes a positive integer representing a duration in seconds as input (e.g.,
+100), and- returns a string which shows the same duration decomposed into weeks, days, hours, minutes, and seconds as detailed below (e.g.,
+1 min, 40 sec).Test Cases- -
-- -input number -output number -- -7259 -- 2 hr, 59 sec- -86400 -- 1 d- - + +6000000 -- 9 wk, 6 d, 10 hr, 40 min+ +input number +output number ++ +7259 ++ 2 hr, 59 sec+ +86400 ++ 1 d+ +6000000 ++ 9 wk, 6 d, 10 hr, 40 minDetails
-The following five units should be used: -- -
-However, only include quantities with non-zero values in the output (e.g., return- -unit -suffix used in output -conversion -- -week -- wk1 week = 7 days -- -day -- d1 day = 24 hours -- -hour -- hr1 hour = 60 minutes -- -minute -- min1 minute = 60 seconds -- - -second -- sec- 1 dand not0 wk, 1 d, 0 hr, 0 min, 0 sec).Give larger units precedence over smaller ones as much as possible (e.g., return2 min, 10 secand not1 min, 70 secor130 sec)Mimic the formatting shown in the test-cases (quantities sorted from largest unit to smallest and separated by comma+space; value and unit of each quantity separated by space). -
+Details++
- + The following five units should be used: +
++ +
++ +unit +suffix used in output +conversion ++ +week ++ wk1 week = 7 days ++ +day ++ d1 day = 24 hours ++ +hour ++ hr1 hour = 60 minutes ++ +minute ++ min1 minute = 60 seconds ++ + +second ++ sec+ - + However, only include quantities with non-zero values in the output (e.g., return
+1 dand not0 wk, 1 d, 0 hr, 0 min, 0 sec). +- + Give larger units precedence over smaller ones as much as possible (e.g., return
+2 min, 10 secand not1 min, 70 secor130 sec). +- + Mimic the formatting shown in the test-cases (quantities sorted from largest unit to smallest and separated by comma+space; value and unit of each quantity separated by space). +
+-Task: - ## Instructions diff --git a/curriculum/challenges/english/08-coding-interview-prep/rosetta-code/count-the-coins.english.md b/curriculum/challenges/english/08-coding-interview-prep/rosetta-code/count-the-coins.english.md index 04f3e5d2c4..2348ac3a3a 100644 --- a/curriculum/challenges/english/08-coding-interview-prep/rosetta-code/count-the-coins.english.md +++ b/curriculum/challenges/english/08-coding-interview-prep/rosetta-code/count-the-coins.english.md @@ -6,22 +6,27 @@ challengeType: 5 ## DescriptionCreate a function, or show a built-in function, to count the number of non-overlapping occurrences of a substring inside a string.
The function should take two arguments:
-the first argument being the string to search, and -the second a substring to be searched for. -It should return an integer count.
-The matching should yield the highest number of non-overlapping matches.
In general, this essentially means matching from left-to-right or right-to-left.
+Create a function, or show a built-in function, to count the number of non-overlapping occurrences of a substring inside a string. +The function should take two arguments: ++
+It should return an integer count. +The matching should yield the highest number of non-overlapping matches. +In general, this essentially means matching from left-to-right or right-to-left.- the first argument being the string to search, and
+- the second a substring to be searched for.
+- ## Instructions diff --git a/curriculum/challenges/english/08-coding-interview-prep/rosetta-code/cramers-rule.english.md b/curriculum/challenges/english/08-coding-interview-prep/rosetta-code/cramers-rule.english.md index c17683e58e..b614340ef6 100644 --- a/curriculum/challenges/english/08-coding-interview-prep/rosetta-code/cramers-rule.english.md +++ b/curriculum/challenges/english/08-coding-interview-prep/rosetta-code/cramers-rule.english.md @@ -6,25 +6,30 @@ challengeType: 5 ## DescriptionThere are four types of common coins in US currency:
-quarters (25 cents) -dimes (10 cents) -nickels (5 cents), and -pennies (1 cent) +There are four types of common coins in US currency: ++
- quarters (25 cents)
+- dimes (10 cents)
+- nickels (5 cents), and
+- pennies (1 cent)
+There are six ways to make change for 15 cents:
-A dime and a nickel -A dime and 5 pennies -3 nickels -2 nickels and 5 pennies -A nickel and 10 pennies -15 pennies -Task: -Implement a function to determine how many ways there are to make change for a dollar using these common coins? (1 dollar = 100 cents).
-Reference: - an algorithm from MIT Press. ++
+Implement a function to determine how many ways there are to make change for a dollar using these common coins? (1 dollar = 100 cents) +Reference: +- A dime and a nickel
+- A dime and 5 pennies
+- 3 nickels
+- 2 nickels and 5 pennies
+- A nickel and 10 pennies
+- 15 pennies
+- ## Instructions diff --git a/curriculum/challenges/english/08-coding-interview-prep/rosetta-code/cut-a-rectangle.md b/curriculum/challenges/english/08-coding-interview-prep/rosetta-code/cut-a-rectangle.md index 61737ed21d..007c5497d9 100644 --- a/curriculum/challenges/english/08-coding-interview-prep/rosetta-code/cut-a-rectangle.md +++ b/curriculum/challenges/english/08-coding-interview-prep/rosetta-code/cut-a-rectangle.md @@ -7,7 +7,11 @@ challengeType: 5 ## DescriptionIn linear algebra, Cramer's rule is an explicit formula for the solution of a system of linear equations with as many equations as unknowns, valid whenever the system has a unique solution. It expresses the solution in terms of the determinants of the (square) coefficient matrix and of matrices obtained from it by replacing one column by the vector of right hand sides of the equations.
-Given
- -$\left\{\begin{matrix}a_1x + b_1y + c_1z&= {\color{red}d_1}\\a_2x + b_2y + c_2z&= {\color{red}d_2}\\a_3x + b_3y + c_3z&= {\color{red}d_3}\end{matrix}\right.$
-which in matrix format is
-$\begin{bmatrix} a_1 & b_1 & c_1 \\ a_2 & b_2 & c_2 \\ a_3 & b_3 & c_3 \end{bmatrix}\begin{bmatrix} x \\ y \\ z \end{bmatrix}=\begin{bmatrix} {\color{red}d_1} \\ {\color{red}d_2} \\ {\color{red}d_3} \end{bmatrix}.$
-Then the values of $x, y$ and $z$ can be found as follows:
-$x = \frac{\begin{vmatrix} {\color{red}d_1} & b_1 & c_1 \\ {\color{red}d_2} & b_2 & c_2 \\ {\color{red}d_3} & b_3 & c_3 \end{vmatrix} } { \begin{vmatrix} a_1 & b_1 & c_1 \\ a_2 & b_2 & c_2 \\ a_3 & b_3 & c_3 \end{vmatrix}}, \quad y = \frac {\begin{vmatrix} a_1 & {\color{red}d_1} & c_1 \\ a_2 & {\color{red}d_2} & c_2 \\ a_3 & {\color{red}d_3} & c_3 \end{vmatrix}} {\begin{vmatrix} a_1 & b_1 & c_1 \\ a_2 & b_2 & c_2 \\ a_3 & b_3 & c_3 \end{vmatrix}}, \text{ and }z = \frac { \begin{vmatrix} a_1 & b_1 & {\color{red}d_1} \\ a_2 & b_2 & {\color{red}d_2} \\ a_3 & b_3 & {\color{red}d_3} \end{vmatrix}} {\begin{vmatrix} a_1 & b_1 & c_1 \\ a_2 & b_2 & c_2 \\ a_3 & b_3 & c_3 \end{vmatrix} }.$
+In linear algebra, Cramer's rule is an explicit formula for the solution of a system of linear equations with as many equations as unknowns, valid whenever the system has a unique solution. It expresses the solution in terms of the determinants of the (square) coefficient matrix and of matrices obtained from it by replacing one column by the vector of right hand sides of the equations. +Given + + $\left\{\begin{matrix}a_1x + b_1y + c_1z&= {\color{red}d_1}\\a_2x + b_2y + c_2z&= {\color{red}d_2}\\a_3x + b_3y + c_3z&= {\color{red}d_3}\end{matrix}\right.$ -Task -Given the following system of equations:
-$\begin{cases} -2w-x+5y+z=-3 \\ -3w+2x+2y-6z=-32 \\ -w+3x+3y-z=-47 \\ -5w-2x-3y+3z=49 \\ -\end{cases}$ -
-solve for $w$, $x$, $y$ and $z$, using Cramer's rule.
+which in matrix format is + + $\begin{bmatrix} a_1 & b_1 & c_1 \\ a_2 & b_2 & c_2 \\ a_3 & b_3 & c_3 \end{bmatrix}\begin{bmatrix} x \\ y \\ z \end{bmatrix}=\begin{bmatrix} {\color{red}d_1} \\ {\color{red}d_2} \\ {\color{red}d_3} \end{bmatrix}.$ + +Then the values of $x, y$ and $z$ can be found as follows: + + $x = \frac{\begin{vmatrix} {\color{red}d_1} & b_1 & c_1 \\ {\color{red}d_2} & b_2 & c_2 \\ {\color{red}d_3} & b_3 & c_3 \end{vmatrix} } { \begin{vmatrix} a_1 & b_1 & c_1 \\ a_2 & b_2 & c_2 \\ a_3 & b_3 & c_3 \end{vmatrix}}, \quad y = \frac {\begin{vmatrix} a_1 & {\color{red}d_1} & c_1 \\ a_2 & {\color{red}d_2} & c_2 \\ a_3 & {\color{red}d_3} & c_3 \end{vmatrix}} {\begin{vmatrix} a_1 & b_1 & c_1 \\ a_2 & b_2 & c_2 \\ a_3 & b_3 & c_3 \end{vmatrix}}, \text{ and }z = \frac { \begin{vmatrix} a_1 & b_1 & {\color{red}d_1} \\ a_2 & b_2 & {\color{red}d_2} \\ a_3 & b_3 & {\color{red}d_3} \end{vmatrix}} {\begin{vmatrix} a_1 & b_1 & c_1 \\ a_2 & b_2 & c_2 \\ a_3 & b_3 & c_3 \end{vmatrix} }.$ + +Task +Given the following system of equations: + + $\begin{cases} + 2w-x+5y+z=-3 \\ + 3w+2x+2y-6z=-32 \\ + w+3x+3y-z=-47 \\ + 5w-2x-3y+3z=49 \\ + \end{cases}$ + +solve for $w$, $x$, $y$ and $z$, using Cramer's rule.A given rectangle is made from m × n squares. If m and n are not both odd, then it is possible to cut a path through the rectangle along the square edges such that the rectangle splits into two connected pieces with the same shape (after rotating one of the pieces by 180°). All such paths for 2 × 2 and 4 × 3 rectangles are shown below. -file:rect-cut.svg + + +Write a function that calculates the number of different ways to cut an m × n rectangle.+ +
+