Added Implementation of sorting algorithms

Author: karthiks2611

Data Structures and Algorithms/Bubble_sort.py

@@ -0,0 +1,21 @@
+
+def BubbleSort(array):
+
+    # Loop to access each array element
+    for i in range(len(array)):
+        for j in range(0,len(array)-1-i):
+            # Replace > with < for descending order
+            if array[j] > array[j+1]:
+
+                # Swapping elements if elements are not in the intended order
+                temp = array[j] 
+                array[j] = array[j+1]
+                array[j+1] = temp
+    return array
+
+
+# Driver code
+if __name__ == '__main__':
+    Array = [-1,9,21,34,1,5,6,8,10,23,25,27,31]
+    print("Array before sorting: ", Array)
+    print("Array after sorting: ", BubbleSort(Array))

Data Structures and Algorithms/Heap_sort.py

@@ -0,0 +1,43 @@
+
+def Heapify(Array, n, i):
+    # Find largest among root and children
+    largest = i
+    l = 2 * i + 1
+    r = 2 * i + 2
+
+    if l < n and Array[l] > Array[largest]:
+        largest = l
+
+    if r < n and Array[r] > Array[largest]:
+        largest = r
+
+    # If root is not largest, swap with largest and continue heapifying
+    if largest != i:
+        Array[i], Array[largest] = Array[largest], Array[i]
+        Heapify(Array, n, largest)
+    
+
+def HeapSort(Array):
+    n = len(Array)
+
+    # Build a max heap
+    for i in range(n//2, -1, -1):
+        Heapify(Array, n, i)
+
+    # One by one extract elements
+    for i in range(n-1, 0, -1):
+        # Swap
+        Array[i], Array[0] = Array[0], Array[i]
+
+        # Heapify root element
+        Heapify(Array, i, 0)
+
+
+if __name__ == "__main__":
+    Array = [-2, -3, -1, 11, 9, 12, 4, -5, -12, 6, 19, 20]
+    HeapSort(Array)
+    n = len(Array)
+    print("Sorted array is")
+    for i in range(n):
+        print("%d " % Array[i], end='')
+  

Data Structures and Algorithms/Selection_sort.py

@@ -0,0 +1,23 @@
+
+def selectionSort(Array, size):
+    
+    for i in range(size):
+        min_indx = i
+
+        for j in range(i+1, size):
+
+            # To sort in descending order, change > to < in this line
+            # Select the minimum element in each loop
+            if Array[j] < Array[min_indx]:
+                min_indx = j
+        
+        # Put minimum eement at the correct position
+        (Array[i], Array[min_indx]) = (Array[min_indx], Array[i])
+    return Array
+
+if __name__ == "__main__":
+    Array = [-2, -3, -1, 11, 9, 12, 4, -5, -12, 6, 19, 20]
+    size = len(Array)
+    print("Array before sorting: ", Array)
+    Array = selectionSort(Array, size)
+    print("Array after sorting: ", Array)