Merge pull request #3 from ranamabdullah/main

software · web-flow · commit 3b73298ba786 · 2021-10-01T23:47:42.000+05:00
added two new algo quick &amp; merge
diff --git a/Other Algorithms/Bubble_Sort.py b/Other Algorithms/Bubble_Sort.py
@@ -0,0 +1,30 @@
+def bubble_sort(array):
+    n = len(array)
+
+    for i in range(n):
+        # Create a flag that will allow the function to
+        # terminate early if there's nothing left to sort
+        already_sorted = True
+
+        # Start looking at each item of the list one by one,
+        # comparing it with its adjacent value. With each
+        # iteration, the portion of the array that you look at
+        # shrinks because the remaining items have already been
+        # sorted.
+        for j in range(n - i - 1):
+            if array[j] > array[j + 1]:
+                # If the item you're looking at is greater than its
+                # adjacent value, then swap them
+                array[j], array[j + 1] = array[j + 1], array[j]
+
+                # Since you had to swap two elements,
+                # set the `already_sorted` flag to `False` so the
+                # algorithm doesn't finish prematurely
+                already_sorted = False
+
+        # If there were no swaps during the last iteration,
+        # the array is already sorted, and you can terminate
+        if already_sorted:
+            break
+
+    return array
diff --git a/Other Algorithms/Merge_Sort.py b/Other Algorithms/Merge_Sort.py
@@ -0,0 +1,39 @@
+def merge(left, right):
+    # If the first array is empty, then nothing needs
+    # to be merged, and you can return the second array as the result
+    if len(left) == 0:
+        return right
+
+    # If the second array is empty, then nothing needs
+    # to be merged, and you can return the first array as the result
+    if len(right) == 0:
+        return left
+
+    result = []
+    index_left = index_right = 0
+
+    # Now go through both arrays until all the elements
+    # make it into the resultant array
+    while len(result) < len(left) + len(right):
+        # The elements need to be sorted to add them to the
+        # resultant array, so you need to decide whether to get
+        # the next element from the first or the second array
+        if left[index_left] <= right[index_right]:
+            result.append(left[index_left])
+            index_left += 1
+        else:
+            result.append(right[index_right])
+            index_right += 1
+
+        # If you reach the end of either array, then you can
+        # add the remaining elements from the other array to
+        # the result and break the loop
+        if index_right == len(right):
+            result += left[index_left:]
+            break
+
+        if index_left == len(left):
+            result += right[index_right:]
+            break
+
+    return result
diff --git a/Other Algorithms/Quick_Sort.py b/Other Algorithms/Quick_Sort.py
@@ -0,0 +1,28 @@
+from random import randint
+
+def quicksort(array):
+    # If the input array contains fewer than two elements,
+    # then return it as the result of the function
+    if len(array) < 2:
+        return array
+
+    low, same, high = [], [], []
+
+    # Select your `pivot` element randomly
+    pivot = array[randint(0, len(array) - 1)]
+
+    for item in array:
+        # Elements that are smaller than the `pivot` go to
+        # the `low` list. Elements that are larger than
+        # `pivot` go to the `high` list. Elements that are
+        # equal to `pivot` go to the `same` list.
+        if item < pivot:
+            low.append(item)
+        elif item == pivot:
+            same.append(item)
+        elif item > pivot:
+            high.append(item)
+
+    # The final result combines the sorted `low` list
+    # with the `same` list and the sorted `high` list
+    return quicksort(low) + same + quicksort(high)
diff --git a/Other Algorithms/Tim_Sort.py b/Other Algorithms/Tim_Sort.py
@@ -0,0 +1,32 @@
+def insertion_sort(array, left=0, right=None):
+    if right is None:
+        right = len(array) - 1
+
+    # Loop from the element indicated by
+    # `left` until the element indicated by `right`
+    for i in range(left + 1, right + 1):
+        # This is the element we want to position in its
+        # correct place
+        key_item = array[i]
+
+        # Initialize the variable that will be used to
+        # find the correct position of the element referenced
+        # by `key_item`
+        j = i - 1
+
+        # Run through the list of items (the left
+        # portion of the array) and find the correct position
+        # of the element referenced by `key_item`. Do this only
+        # if the `key_item` is smaller than its adjacent values.
+        while j >= left and array[j] > key_item:
+            # Shift the value one position to the left
+            # and reposition `j` to point to the next element
+            # (from right to left)
+            array[j + 1] = array[j]
+            j -= 1
+
+        # When you finish shifting the elements, position
+        # the `key_item` in its correct location
+        array[j + 1] = key_item
+
+    return array
