Added merge-sort in MATLAB (#27783)

* Added merge-sort in MATLAB

* fix: changed c++ to cpp

guide/english/algorithms/sorting-algorithms/merge-sort/index.md

@@ -52,15 +52,6 @@ If right > l:
 * <a href='https://www.cs.usfca.edu/~galles/visualization/ComparisonSort.html'>USFCA</a>
 * <a href='https://www.hackerearth.com/practice/algorithms/sorting/merge-sort/visualize/'>HackerEarth</a>
 
-
-### Relavant videos on freeCodeCamp YouTube channel
-* <a href='https://youtu.be/TzeBrDU-JaY'>Merge Sort algorithm - MyCodeSchool</a>
-
-### Other Resources:
-* <a href='https://en.wikipedia.org/wiki/Merge_sort' target='_blank' rel='nofollow'>Wikipedia</a>
-* <a href='www.geeksforgeeks.org/merge-sort' target='_blank' rel='nofollow'>GeeksForGeeks</a>
-* <a href='https://youtu.be/sWtYJv_YXbo' target='_blank' rel='nofollow'>Merge Sort - CS50</a>
-
 ### Implementaion in JS
 ```js
 const list = [23, 4, 42, 15, 16, 8, 3]
@@ -182,6 +173,32 @@ int main()
 
 ### Implementation in C++
  
+Let us consider array A = {2,5,7,8,9,12,13}
+and array B = {3,5,6,9,15} and we want array C to be in ascending order as well.
+
+```cpp
+void mergesort(int A[],int size_a,int B[],int size_b,int C[])
+{
+     int token_a,token_b,token_c;
+     for(token_a=0, token_b=0, token_c=0; token_a<size_a && token_b<size_b; )
+     {
+          if(A[token_a]<=B[token_b])
+               C[token_c++]=A[token_a++];
+          else
+               C[token_c++]=B[token_b++];
+      }
+      
+      if(token_a<size_a)
+      {
+          while(token_a<size_a)
+               C[token_c++]=A[token_a++];
+      }
+      else
+      {
+          while(token_b<size_b)
+               C[token_c++]=B[token_b++];
+      }
+
 ```cpp
 void merge(int arr[], int l, int m, int r) 
 { 
@@ -391,3 +408,57 @@ public class mergesort {
   }
 }
 ```
+
+### Implementaion in MATLAB
+```matlab
+
+a = [9,4,7,3,8,5,1,6,2];
+
+[sorted] = mergeSort(a);
+
+function [sorted] = mergeSort(unsorted)
+    len = length(unsorted);
+    if len == 1
+        sorted = unsorted;
+        return;
+    end
+    mid = ceil((len)/2);
+    left = mergeSort(unsorted(1:mid));
+    right = mergeSort(unsorted(mid+1:end));
+    
+    sorted = mergeLR(left, right);
+       
+end
+
+function [sorted] = mergeLR(left, right)
+    sorted = [left right];                              % add two splited array together
+    j = 1;                                              % index for 'sorted'
+    k = 1;                                              % index for 'left'
+    for i = 1:1:length(right)
+        % going through every element of the 'right'
+        if right(i) < left(k)
+            sorted(j) = right(i);                       % move the 'right' element before 
+            sorted(j+1:(j+length(left(k:end)))) = left(k:end);      % shift the left elemts 
+            j = j+1;
+        else
+            while (k <= length(left)) && (right(i) > left(k))
+                k = k+1;
+                j = j+1;
+            end
+            sorted(j) = right(i);
+            sorted(j+1:(j+length(left(k:end)))) = left(k:end);
+            j = j+1;
+        end
+    end
+
+end
+
+```
+
+### Relavant videos on freeCodeCamp YouTube channel
+* <a href='https://youtu.be/TzeBrDU-JaY'>Merge Sort algorithm - MyCodeSchool</a>
+
+### Other Resources:
+* <a href='https://en.wikipedia.org/wiki/Merge_sort' target='_blank' rel='nofollow'>Wikipedia</a>
+* <a href='www.geeksforgeeks.org/merge-sort' target='_blank' rel='nofollow'>GeeksForGeeks</a>
+* <a href='https://youtu.be/sWtYJv_YXbo' target='_blank' rel='nofollow'>Merge Sort - CS50</a>