Bubble Sort Two Dimensional Array - ruby

Question

I've been implementing an exercise on bubbling sorting.
So far, managed to bubble sort through an array.
Let's say, we have our array = ([5,6,7], [2,3,4])
How can I bubble sort through this without modifying the original array or using sort?
The exercise requires that I do not copy/duplicate/clone/edit or use a sort method.
My code to bubble sort through a regular array:
def bubble_sort(array)
is_sorted = false
until is_sorted
is_sorted = true
(array.count - 1).times do |i|
if array[i] > array[i + 1]
array[i], array[i + 1] = array[i + 1], array[i]
is_sorted = false
end
end
end
end
arr

Answer 1

As usual I learned quite a lot solving the OPs homework :-)
Firstly "do not copy/duplicate/clone/edit or use a sort method" just means that you have to implement your own algorithm. It does not mean you shouldn't copy the array passed to your function. You must copy your original array to avoid the side effect of modifying the original array.
However! if you simply copy the array new_array = array ruby will copy by reference.
That means that both variables will still point to the same data structure. Your sort will happily sort the numbers and the array passed as a parameter will be modified.
To fix this you need to copy the array using the dup function.
new_array = array.dup
Then the bubble sort function ends up looking like this:
def bubble_sort(array)
result = array.dup
begin
sorted = true
(0..result.length - 2).each do |i|
if result[i] > result[i + 1]
result[i], result[i+1] = result[i+1], result[i]
sorted = false
end
end
end while !sorted
result
end
Some test code:
a = [9,8,7,6,5,5,9,]
puts "array before sorting:"
puts a.inspect
puts "sorted array returned by function"
puts bubble_sort(a).inspect
puts "original array after sorting:"
puts a.inspect
Resulting output:
>ruby mysort.rb
array before sorting:
[9, 8, 7, 6, 5, 5, 9]
sorted array returned by function
[5, 5, 6, 7, 8, 9, 9]
original array after sorting:
[9, 8, 7, 6, 5, 5, 9]

Answer 2

Create a new array that is a copy of the original and sort that. That will let you keep the original array and have the sorted array.

Answer 3

Can you just combine the two arrays into a single array and then run a typical bubble sort?
def combine_arrays(arr1,arr2)
final = arr1 + arr2
sorted = true
while sorted do
sorted = false
(0..final.length - 2).each do |x|
if final[x] > final[x+1]
final[x], final[x+1] = final[x+1], final[x]
sorted = true
end
end
end
final
end
p combine_arrays([1,3,5],[2,4,6]) => [1, 2, 3, 4, 5, 6]

Answer 4

i think the simplest way for Bubble Sorting multi Dimensional Arrays is:
int main()
{
const size_t row = 4,col=6;
int temp;
int arr[row][col] = { { 6, 5, 4, 3, 2, 1 }, { 12, 11, 10, 9, 8, 7 }, {18, 17, 16, 15, 14, 13 }, { 24,23,22,21,20,1 } };
for (auto &row : arr)
{
for (int i = 0; i != col; ++i)
{
int flag = 0;
for (int j = 0; j != col-i - 1; ++j)
{
if (row[j]>row[j+1])
{
temp = row[j];
row[j] = row[j + 1];
row[j + 1] = temp;
flag = 1;
}
}
if (!flag)break;
}
}
for (auto &row : arr)
{
for (auto col : row)
cout << col << " ";
cout << endl;
}
return 0;
}