/
mergesort.py
36 lines (30 loc) · 905 Bytes
/
mergesort.py
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class MergeSort:
def sort(self, array):
if array is None:
raise TypeError('array cannot be None')
return self._sort(array)
def _sort(self, array):
if len(array) < 2:
return array
mid = len(array)//2
left = self._sort(array[:mid])
right = self._sort(array[mid:])
return self._merge(left, right)
def _merge(self, left, right):
l = 0
r = 0
new_array = []
while l < len(left) and r < len(right):
if left[l] < right[r]:
new_array.append(left[l])
l += 1
else:
new_array.append(right[r])
r += 1
while l < len(left):
new_array.append(left[l])
l += 1
while r < len(right):
new_array.append(right[r])
r += 1
return new_array