Ruby implements three fast sorting algorithms:

Ruby implements three fast sorting algorithms:

I just learned Ruby. It happened that the algorithm teacher encouraged me to write algorithms in unfamiliar languages. I will use Ruby ~~
Ruby is really amazing, and many intuitive methods can be used ..... Infinite worship ....

While I encountered an invalid multibyte char (US-ASCII) error, the solution is to add a # encoding: UTF-8 at the beginning
This error was asked by someone on stackoverflow. The answer Someone gave is:
Write # encoding: UTF-8 on top of that file. That changes the default encoding of all string/regexp literals in that file UTF-8.
Reference: http://stackoverflow.com/questions/3678172/ruby-1-9-invalid-multibyte-char-us-ascii

Common Quick Sort versions:

Copy codeThe Code is as follows:
# Encoding: UTF-8
# Author: xu jin 4100213
# Date: Oct 20,201 2
# RandomizedQuickSort
# To sort an array by using QuickSort
# Example:
# The original array is: [10, 35, 25, 67, 69, 52, 24, 40, 69, 76, 6, 49]
# The sorted array is: [6, 10, 24, 25, 35, 40, 49, 52, 67, 69, 69, 76]

ArrayInt = Array. new
Index = 0
While (index <12)
ArrayInt [index] = rand (100) # produce 12 random number
Index + = 1
End
Puts "The original array is:" + arrayInt. to_s

Def QuickSort (arrayInt, first, last)
If first <last
Middle = Partition (arrayInt, first, last)
QuickSort (arrayInt, first, middle-1)
QuickSort (arrayInt, middle + 1, last)
End
End

Def Partition (arrayInt, first, last)
X = arrayInt [last]
I = first-1
For j in first... (last-1)
If arrayInt [j] <= x
I + = 1
ArrayInt [I], arrayInt [j] = arrayInt [j], arrayInt [I] # exchange
End
End
ArrayInt [I + 1], arrayInt [last] = arrayInt [last], arrayInt [I + 1]
Return I + 1
End

QuickSort (arrayInt, 0, arrayInt. length-1)
Puts "The sorted array is:" + arrayInt. to_s

Randomization version of Quick Sort:
Copy codeThe Code is as follows:
# Encoding: UTF-8
# Author: xu jin 4100213
# Date: Oct 20,201 2
# RandomizedQuickSort
# To sort an array by using randomized QuickSort
# Example:
# The original array is: [14, 47, 46, 49, 82, 76, 92, 22, 44, 81, 59, 61]
# The sorted array is: [14, 22, 44, 46, 47, 49, 59, 61, 76, 81, 82, 92]

ArrayInt = Array. new
Index = 0
While (index <12)
ArrayInt [index] = rand (100) # produce 12 random number
Index + = 1
End
Puts "The original array is:" + arrayInt. to_s

Def RandomizedQuickSort (arrayInt, first, last)
If first <last
Middle = RandomizedPartition (arrayInt, first, last)
RandomizedQuickSort (arrayInt, first, middle-1)
RandomizedQuickSort (arrayInt, middle + 1, last)
End
End

Def RandomizedPartition (arrayInt, first, last)
I = rand (last-first + 1) + first
ArrayInt [I], arrayInt [last] = arrayInt [last], arrayInt [I]
Return Partition (arrayInt, first, last)
End

Def Partition (arrayInt, first, last)
X = arrayInt [last]
I = first-1
For j in first... (last-1)
If arrayInt [j] <= x
I + = 1
ArrayInt [I], arrayInt [j] = arrayInt [j], arrayInt [I] # exchange
End
End
ArrayInt [I + 1], arrayInt [last] = arrayInt [last], arrayInt [I + 1]
Return I + 1
End

RandomizedQuickSort (arrayInt, 0, arrayInt. length-1)
Puts "The sorted array is:" + arrayInt. to_s

The quick sorting utilizes the random version of the Ruby syntax sugar:

Copy codeThe Code is as follows:
# Encoding: UTF-8
# Author: xu jin 4100213
# Date: Oct 20,201 2
# RandomizedQuickSort
# To sort an array by using randomized QuickSort
# Example:
# The original array is: [14, 47, 46, 49, 82, 76, 92, 22, 44, 81, 59, 61]
# The sorted array is: [14, 22, 44, 46, 47, 49, 59, 61, 76, 81, 82, 92]

ArrayInt = Array. new
Index = 0
While (index <12)
ArrayInt [index] = rand (100) # produce 12 random number
Index + = 1
End
Puts "The original array is:" + arrayInt. to_s

Def RandomizedQuickSort ()
I = rand (a. length)
A [I], a [a. length-1] = a [a. length-1], a [I]
(X = a. pop )? RandomizedQuickSort (a. select {| I <= x}) + [x] + RandomizedQuickSort (a. select {| I> x}): []
End

Puts "The sorted array is:" + RandomizedQuickSort (arrayInt). to_s