Merge Sort without Slicing

Basically in merge sort we use slice function so the above code is similat to quick sort which helps merge sort to use without slicing

sorting/MergesortWithoutSlicing.py

@@ -0,0 +1,60 @@
+
+# coding: utf-8
+
+# In[1]:
+
+
+#Merge Slot Without Slicing
+#start is the index of the first item
+#end is the index past the the last item
+def indexMergeSort(alist, start = None, end = None):
+    if start == None:
+        start = 0
+    if end == None:
+        end = len(alist)  
+    #note that the print operations still use slicing for convenience
+    #print("Input: ",alist[start:end])
+    
+    length = end - start
+    if length > 1:
+        #print("Splitting ",alist[start:end])
+        mid = start + length//2
+        
+        indexMergeSort(alist, start, mid)
+        indexMergeSort(alist, mid, end)
+
+        i=start # index for the left part of the list
+        j=mid # index for the right part of the list
+        #we use a temporary list
+        templist = [None] * (length)
+        k = 0 #index for the temp list
+        while i < mid and j < end:
+            if alist[i] < alist[j]:
+                templist[k] = alist[i]
+                i=i+1
+            else:
+                #we swap
+                templist[k] = alist[j]
+                j=j+1
+            k=k+1
+
+        while i < mid:
+            templist[k] = alist[i]
+            i=i+1
+            k=k+1
+
+        while j < end:
+            templist[k]=alist[j]
+            j=j+1
+            k=k+1
+        
+        #we copy the results
+        for k in range(length):
+            alist[start+k] = templist[k]
+            
+        #print("Merging ",alist[start:mid], alist[mid:end])
+
+alist = [54,26,93,17,77,31,44,55,20]
+indexMergeSort(alist)
+print(alist)
+