Python merge sort
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In Algorithms Fourth Edition by Robert Sedgewick and Kevin Wayne, the exercise 2.2.10 states that:
Implement a version of merge() that copies the second half of a to
aux in decreasing order and then does the merge back to a. This
change al- lows you to remove the code to test that each of the halves
has been exhausted from the inner loop.
This is my code in Python:
def merge(a, lo, mi, hi):
aux_hi = deque(a[mi:hi])
for i in range(lo, hi)[::-1]：
if aux_hi:
last_a = i-len(aux_hi)
if last_a < lo:
a[i] = aux_hi.pop()
else:
a[i] = aux_hi.pop() if aux_hi[-1] > a[last_a] else a[last_a]
else:
break
Have I implemented it as required? Or can it be improved further?
python algorithm sorting mergesort
edited 8 mins ago
Jamal♦
30.2k11115226
asked 6 hours ago
lerner
1265
add a comment |
up vote
0
down vote
favorite
In Algorithms Fourth Edition by Robert Sedgewick and Kevin Wayne, the exercise 2.2.10 states that:
Implement a version of merge() that copies the second half of a to
aux in decreasing order and then does the merge back to a. This
change al- lows you to remove the code to test that each of the halves
has been exhausted from the inner loop.
This is my code in Python:
def merge(a, lo, mi, hi):
aux_hi = deque(a[mi:hi])
for i in range(lo, hi)[::-1]：
if aux_hi:
last_a = i-len(aux_hi)
if last_a < lo:
a[i] = aux_hi.pop()
else:
a[i] = aux_hi.pop() if aux_hi[-1] > a[last_a] else a[last_a]
else:
break
Have I implemented it as required? Or can it be improved further?
python algorithm sorting mergesort
edited 8 mins ago
Jamal♦
30.2k11115226
asked 6 hours ago
lerner
1265
add a comment |
up vote
0
down vote
favorite
up vote
0
down vote
favorite
In Algorithms Fourth Edition by Robert Sedgewick and Kevin Wayne, the exercise 2.2.10 states that:
Implement a version of merge() that copies the second half of a to
aux in decreasing order and then does the merge back to a. This
change al- lows you to remove the code to test that each of the halves
has been exhausted from the inner loop.
This is my code in Python:
def merge(a, lo, mi, hi):
aux_hi = deque(a[mi:hi])
for i in range(lo, hi)[::-1]：
if aux_hi:
last_a = i-len(aux_hi)
if last_a < lo:
a[i] = aux_hi.pop()
else:
a[i] = aux_hi.pop() if aux_hi[-1] > a[last_a] else a[last_a]
else:
break
Have I implemented it as required? Or can it be improved further?
python algorithm sorting mergesort
edited 8 mins ago
Jamal♦
30.2k11115226
asked 6 hours ago
lerner
1265
In Algorithms Fourth Edition by Robert Sedgewick and Kevin Wayne, the exercise 2.2.10 states that:
Implement a version of merge() that copies the second half of a to
aux in decreasing order and then does the merge back to a. This
change al- lows you to remove the code to test that each of the halves
has been exhausted from the inner loop.
This is my code in Python:
def merge(a, lo, mi, hi):
aux_hi = deque(a[mi:hi])
for i in range(lo, hi)[::-1]：
if aux_hi:
last_a = i-len(aux_hi)
if last_a < lo:
a[i] = aux_hi.pop()
else:
a[i] = aux_hi.pop() if aux_hi[-1] > a[last_a] else a[last_a]
else:
break
Have I implemented it as required? Or can it be improved further?
python algorithm sorting mergesort
python algorithm sorting mergesort
edited 8 mins ago
Jamal♦
30.2k11115226
asked 6 hours ago
lerner
1265
edited 8 mins ago
Jamal♦
30.2k11115226
asked 6 hours ago
lerner
1265
edited 8 mins ago
Jamal♦
30.2k11115226
edited 8 mins ago
Jamal♦
30.2k11115226
edited 8 mins ago
Jamal♦
30.2k11115226
30.2k11115226
asked 6 hours ago
lerner
1265
asked 6 hours ago
lerner
1265
asked 6 hours ago
lerner
1265
1265
add a comment |
add a comment |
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