def merge_sort(alist, start, end):
'''Sorts the list from indexes start to end - 1 inclusive.'''
if end - start > 1:
mid = (start + end)//2
merge_sort(alist, start, mid)
merge_sort(alist, mid, end)
merge_list(alist, start, mid, end)
def merge_list(alist, start, mid, end):
left = alist[start:mid]
right = alist[mid:end]
k = start
i = 0
j = 0
while (start + i < mid and mid + j < end):
if (left[i] <= right[j]):
alist[k] = left[i]
i = i + 1
else:
alist[k] = right[j]
j = j + 1
k = k + 1
if start + i < mid:
while k < end:
alist[k] = left[i]
i = i + 1
k = k + 1
else:
while k < end:
alist[k] = right[j]
j = j + 1
k = k + 1
alist = input('Enter the list of numbers: ').split()
alist = [int(x) for x in alist]
merge_sort(alist, 0, len(alist))
print('Sorted list: ', end='')
print(alist)
def merge_sort(alist, start, end): '''Sorts the list from indexes start to end - 1 inclusive.''' if end - start > 1: mid = (start + end)//2 merge_sort(alist, start, mid) merge_sort(alist, mid, end) merge_list(alist, start, mid, end)
def merge_list(alist, start, mid, end): left = alist[start:mid] right = alist[mid:end] k = start i = 0 j = 0 while (start + i < mid and mid + j < end): if (left[i] <= right[j]): alist[k] = left[i] i = i + 1 else: alist[k] = right[j] j = j + 1 k = k + 1 if start + i < mid: while k < end: alist[k] = left[i] i = i + 1 k = k + 1 else: while k < end: alist[k] = right[j] j = j + 1 k = k + 1
alist = input('Enter the list of numbers: ').split() alist = [int(x) for x in alist] merge_sort(alist, 0, len(alist)) print('Sorted list: ', end='') print(alist)