Refactor bubble sort implementation for improved readability and performance

code/sorting/src/bubble_sort/bubble_sort.py

@@ -2,40 +2,27 @@
 
 
 def bubble_sort(arr):
-    """
-    >>> arr = [5, 1, 3, 9, 2]
-    >>> bubble_sort(arr)
-    >>> arr
-    [1, 2, 3, 5, 9]
-    """
-    for i in range(len(arr)):
-       # Terminate algorithm if no more swaps are to be carried out
-       is_sorted = True 
-       for j in range(i + 1, len(arr)):
-           # If current(ith) element is greater than the next((i+1)th) element swap them
-           if arr[i] > arr[j]:
-              arr[i], arr[j] = arr[j], arr[i]
-              is_sorted = False
-       if is_sorted:
-           break
-
-
-# Less elegant solution, but easier to follow along:
-def bubble_sort(alist):
-    # flag to keep track of whether the list is sorted or not, initially it is set as false
-    is_sorted = False
-    # keep comparing till the list is sorted
-    while not is_sorted:
-        num_swaps = 0
-        # iterate through all the elements(except the last) in the list
-        for i in range(len(alist) - 1):
-            # if the current element is greater than the next element, pop it out of the list 
-            if alist[i] > alist[i + 1]:
-                a = alist.pop(i + 1)
-                # insert the popped element to its right position in the list
-                alist.insert(i, a)
-                num_swaps += 1
-        # if the list is sorted, no more swaps are carried out
-        if num_swaps == 0:
-            is_sorted = True
-    return alist
+    n = len(arr)
+
+    for i in range(n):
+        # Last i elements are already in place
+        for j in range(0, n - i - 1):
+            # Traverse the array from 0 to n-i-1
+            # Swap if the element found is greater than the next element
+            if arr[j] > arr[j + 1]:
+                arr[j], arr[j + 1] = arr[j + 1], arr[j]
+
+    return arr
+
+
+# Example usage
+if __name__ == "__main__":
+    # Just an example list to test with
+    arr = [64, 34, 25, 12, 22, 11, 90]
+    print("Original array:", arr)  # Output: [64, 34, 25, 12, 22, 11, 90]
+
+    # Run the bubble sort
+    bubble_sort(arr)
+
+    # Print out the sorted list
+    print("Sorted array:", arr)  # Output: [11, 12, 22, 25, 34, 64, 90]