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Tighten up psf/black and flake8 (#2024)

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* Tighten up psf/black and flake8

* Fix some tests

* Fix some E741

* Fix some E741

* updating DIRECTORY.md

Co-authored-by: github-actions <${GITHUB_ACTOR}@users.noreply.github.com>
This commit is contained in:
Christian Clauss
2020-05-22 08:10:11 +02:00
committed by GitHub
parent 21ed8968c0
commit 1f8a21d727
124 changed files with 583 additions and 495 deletions
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16
backtracking/n_queens.py
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@ -1,9 +1,9 @@
"""
The nqueens problem is of placing N queens on a N * N
The nqueens problem is of placing N queens on a N * N
chess board such that no queen can attack any other queens placed
on that chess board.
This means that one queen cannot have any other queen on its horizontal, vertical and
This means that one queen cannot have any other queen on its horizontal, vertical and
diagonal lines.
"""
@ -12,7 +12,7 @@ solution = []
def isSafe(board, row, column):
"""
This function returns a boolean value True if it is safe to place a queen there considering
This function returns a boolean value True if it is safe to place a queen there considering
the current state of the board.
Parameters :
@ -40,13 +40,13 @@ def isSafe(board, row, column):
def solve(board, row):
"""
It creates a state space tree and calls the safe function until it receives a
False Boolean and terminates that branch and backtracks to the next
It creates a state space tree and calls the safe function until it receives a
False Boolean and terminates that branch and backtracks to the next
possible solution branch.
"""
if row >= len(board):
"""
If the row number exceeds N we have board with a successful combination
If the row number exceeds N we have board with a successful combination
and that combination is appended to the solution list and the board is printed.
"""
@ -56,9 +56,9 @@ def solve(board, row):
return
for i in range(len(board)):
"""
For every row it iterates through each column to check if it is feasible to place a
For every row it iterates through each column to check if it is feasible to place a
queen there.
If all the combinations for that particular branch are successful the board is
If all the combinations for that particular branch are successful the board is
reinitialized for the next possible combination.
"""
if isSafe(board, row, i):