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Mergesort.py
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Mergesort.py
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def mergesort(data):
if len(data) <= 1:
return data
mid = len(data)//2
left = mergesort(data[:mid])
right = mergesort(data[mid:])
return merge(left, right)
def merge(left, right):
aux = []
i = j = 0
while i < len(left) and j < len(right):
if left[i] <= right[j]:
aux.append(left[i])
i += 1
else:
aux.append(right[j])
j += 1
# DO THE FOR LOOPS NOT THIS TO IMPROVE MEMORY COST
if i < len(left):
aux += left[i:]
else:
aux += right[j:]
return aux
arr = [12, 11, 13, 5, 6, 7]
print(mergesort(arr))
UPDATE:
a = [5, 2, 3, 1, 4]
def mergesort(nums):
if len(nums) <= 1:
return nums
mid = len(nums)//2
left = mergesort(nums[: mid])
right = mergesort(nums[mid:])
return partition(left, right)
def partition(left, right):
result = []
l = 0
r = 0
while l < len(left) and r < len(right):
if left[l] <= right[r]:
result.append(left[l])
l += 1
else:
result.append(right[r])
r += 1
if l < len(left):
for item in range(l, len(left)):
result.append(left[item])
if r < len(right):
for item in range(r, len(right)):
result.append(right[item])
return result
print(mergesort(a))