Merge ShellSort

sorting.py

@@ -3,7 +3,7 @@ Carlos J Corrada Bravo
 Este programa calcula el promedio de tiempo de ejecucion de cuatro algoritmos de ordenamiento
 La variable maxValor define el valor maximo de los elementos de la lista
 La variable largoLista define el largo de las listas a ordenar
-La variable veces define las veces que se va a hacer el ordenamiento 
+La variable veces define las veces que se va a hacer el ordenamiento
 Al final se imprimen los promedios de cada algortimo
 """
 from random import randint
@@ -11,7 +11,56 @@ import time
 
 def mergeSort(lista):
 	#definan el algoritmo de ordenamiento mergesort
+	# If the size of the list is greater than 1 then it enters here
+	if len(lista) > 1:
+		# Gets the half of the list
+		Midd = len(lista) / 2
+		# Takes only the elements that are in the left of the list
+		Left = lista[Midd:]
+		# If the size of left still is not 1 then
+		if len(Left) != 1:
+			# it will do a recursive call to the function again
+			mergeSort(Left)
+		# Takes only the elements that are in the right of the list
+		Right = lista[:Midd]
+		# If the size of right still is not 1 then
+		if len(Right) != 1:
+			# it will do a recursive call to the function again
+			mergeSort(Right)
+
+		# Variables define for while and getting space in the list
+        i = j = k = 0
+
+		# While i and j are less than the comparation it enters here
+        while i < len(Left) and j < len(Right):
+			# If the compared number in i is less than j it enters here
+            if Left[i] < Right[j]:
+				# The less variable is stored in the list again in order
+                lista[k] = Left[i]
+                i += 1 # Increments i
+			# If the compared number in i is greater than j it enters here
+            else:
+				# The less variable is stored in the list again in order
+                lista[k] = Right[j]
+                j += 1 # Increments j
+            k += 1 # Increments k
+
+		# If there are elements remaining in Left the they are put here
+        while i < len(Left):
+			# The variable that was remaining is put here
+            lista[k] = Left[i]
+            i += 1 # Increments i
+            k += 1 # Increments k
+
+		# If there are elements remaining in Right the they are put here
+        while j < len(Right):
+			# The variable that was remaining is put here
+            lista[k] = Right[j]
+            j += 1 # Increments j
+            k += 1 # Increments k
+
 	return lista
+	# Code was base and taken from GeeksforGeeks
 
 def heapSort(lista):
 	#definan el algoritmo de ordenamiento heapsort
@@ -23,11 +72,33 @@ def quickSort(lista):
 
 def shellSort(lista):
 	#definan el algoritmo de ordenamiento shellsort
+	Size = len(lista) # Contains the complete size of the list
+	Diff = Size/2 # Contains the number of half of the list
+
+	# Does a insertion sort by ordering in base of the Diff.
+	while Diff > 0:
+		# Begins a loop to sort the elements added to sorted array.
+		for i in range(Diff, Size):
+			# Saves the element sorted in a temporary variable
+			Tmp = lista[i]
+			j = i # Shifts the location of the elements
+			# Looks for the locations
+			while j >= Diff and lista[j - Diff] > Tmp:
+				# Gives the new element to the location
+				lista[j] = lista[j - Diff]
+				# The size of the array is ajusted
+				j -= Diff
+			# Puts the Tmp variable in is correct location
+			lista[j] = Tmp
+		# Reduces again the list
+		Diff /= 2
+
 	return lista
+	# Code was taken from GeeksforGeeks
 
 maxValor=1000 	#define el valor maximo de los elementos de la lista
 largoLista=1000 #define el largo de las listas a ordenar
-veces=100 		#define las veces que se va a hacer el ordenamiento 
+veces=100 		#define las veces que se va a hacer el ordenamiento
 
 acumulaMerge=0 	#variable para acumular el tiempo de ejecucion del mergesort
 acumulaHeap=0 	#variable para acumular el tiempo de ejecucion del heapsort
@@ -43,15 +114,15 @@ for i in range(veces):
 	t1 = time.clock() 				#seteamos el tiempo al empezar
 	mergeSort(mergelista) 				#ejecutamos el algoritmo mergeSort
 	acumulaMerge+=time.clock()-t1 	#acumulamos el tiempo de ejecucion
-	
+
 	t1 = time.clock()				#seteamos el tiempo al empezar
 	heapSort(heaplista)					#ejecutamos el algoritmo heapSort
 	acumulaHeap+=time.clock()-t1 	#acumulamos el tiempo de ejecucion
-	
+
 	t1 = time.clock()				#seteamos el tiempo al empezar
 	quickSort(quicklista)				#ejecutamos el algoritmo quickSort
 	acumulaQuick+=time.clock()-t1 	#acumulamos el tiempo de ejecucion
-	
+
 	t1 = time.clock()				#seteamos el tiempo al empezar
 	shellSort(searchlista)				#ejecutamos el algoritmo shellSort
 	acumulaShell+=time.clock()-t1 	#acumulamos el tiempo de ejecucion
@@ -62,4 +133,3 @@ print "MergeSort " + str(acumulaMerge/veces) + " segundos"
 print "HeapSort " + str(acumulaHeap/veces) + " segundos"
 print "QuickSort " + str(acumulaQuick/veces) + " segundos"
 print "ShellSort " + str(acumulaShell/veces) + " segundos"
-