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Set the Python file maximum line length to 88 characters (#2122)

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* flake8 --max-line-length=88

* fixup! Format Python code with psf/black push

Co-authored-by: github-actions <${GITHUB_ACTOR}@users.noreply.github.com>
This commit is contained in:
Christian Clauss
2020-06-16 10:09:19 +02:00
committed by GitHub
parent 9438c6bf0b
commit 9316e7c014
90 changed files with 473 additions and 320 deletions
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29
dynamic_programming/rod_cutting.py
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@ -13,8 +13,9 @@ pieces separately or not cutting it at all if the price of it is the maximum obt
def naive_cut_rod_recursive(n: int, prices: list):
"""
Solves the rod-cutting problem via naively without using the benefit of dynamic programming.
The results is the same sub-problems are solved several times leading to an exponential runtime
Solves the rod-cutting problem via naively without using the benefit of dynamic
programming. The results is the same sub-problems are solved several times
leading to an exponential runtime
Runtime: O(2^n)
@ -26,7 +27,8 @@ def naive_cut_rod_recursive(n: int, prices: list):
Returns
-------
The maximum revenue obtainable for a rod of length n given the list of prices for each piece.
The maximum revenue obtainable for a rod of length n given the list of prices
for each piece.
Examples
--------
@ -50,8 +52,9 @@ def naive_cut_rod_recursive(n: int, prices: list):
def top_down_cut_rod(n: int, prices: list):
"""
Constructs a top-down dynamic programming solution for the rod-cutting problem
via memoization. This function serves as a wrapper for _top_down_cut_rod_recursive
Constructs a top-down dynamic programming solution for the rod-cutting
problem via memoization. This function serves as a wrapper for
_top_down_cut_rod_recursive
Runtime: O(n^2)
@ -63,12 +66,13 @@ def top_down_cut_rod(n: int, prices: list):
Note
----
For convenience and because Python's lists using 0-indexing, length(max_rev) = n + 1,
to accommodate for the revenue obtainable from a rod of length 0.
For convenience and because Python's lists using 0-indexing, length(max_rev) =
n + 1, to accommodate for the revenue obtainable from a rod of length 0.
Returns
-------
The maximum revenue obtainable for a rod of length n given the list of prices for each piece.
The maximum revenue obtainable for a rod of length n given the list of prices
for each piece.
Examples
-------
@ -99,7 +103,8 @@ def _top_down_cut_rod_recursive(n: int, prices: list, max_rev: list):
Returns
-------
The maximum revenue obtainable for a rod of length n given the list of prices for each piece.
The maximum revenue obtainable for a rod of length n given the list of prices
for each piece.
"""
if max_rev[n] >= 0:
return max_rev[n]
@ -144,7 +149,8 @@ def bottom_up_cut_rod(n: int, prices: list):
"""
_enforce_args(n, prices)
# length(max_rev) = n + 1, to accommodate for the revenue obtainable from a rod of length 0.
# length(max_rev) = n + 1, to accommodate for the revenue obtainable from a rod of
# length 0.
max_rev = [float("-inf") for _ in range(n + 1)]
max_rev[0] = 0
@ -167,7 +173,8 @@ def _enforce_args(n: int, prices: list):
Throws ValueError:
if n is negative or there are fewer items in the price list than the length of the rod
if n is negative or there are fewer items in the price list than the length of
the rod
"""
if n < 0:
raise ValueError(f"n must be greater than or equal to 0. Got n = {n}")