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contribution guidelines checks (#1787)

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* spelling corrections

* review

* improved documentation, removed redundant variables, added testing

* added type hint

* camel case to snake case

* spelling fix

* review

* python --> Python # it is a brand name, not a snake

* explicit cast to int

* spaces in int list

* "!= None" to "is not None"

* Update comb_sort.py

* various spelling corrections in documentation & several variables naming conventions fix

* + char in file name

* import dependency - bug fix

Co-authored-by: John Law <johnlaw.po@gmail.com>
This commit is contained in:
matkosoric
2020-03-04 13:40:28 +01:00
committed by GitHub
parent 2b19e84767
commit 7f04e5cd34
57 changed files with 198 additions and 198 deletions
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dynamic_programming/bitmask.py
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@ -1,6 +1,6 @@
"""
This is a python implementation for questions involving task assignments between people.
This is a Python implementation for questions involving task assignments between people.
Here Bitmasking and DP are used for solving this.
Question :-
@ -25,41 +25,41 @@ class AssignmentUsingBitmask:
self.task = defaultdict(list) # stores the list of persons for each task
# finalmask is used to check if all persons are included by setting all bits to 1
self.finalmask = (1 << len(task_performed)) - 1
# final_mask is used to check if all persons are included by setting all bits to 1
self.final_mask = (1 << len(task_performed)) - 1
def CountWaysUtil(self, mask, taskno):
def CountWaysUtil(self, mask, task_no):
# if mask == self.finalmask all persons are distributed tasks, return 1
if mask == self.finalmask:
if mask == self.final_mask:
return 1
# if not everyone gets the task and no more tasks are available, return 0
if taskno > self.total_tasks:
if task_no > self.total_tasks:
return 0
# if case already considered
if self.dp[mask][taskno] != -1:
return self.dp[mask][taskno]
if self.dp[mask][task_no] != -1:
return self.dp[mask][task_no]
# Number of ways when we don't this task in the arrangement
total_ways_util = self.CountWaysUtil(mask, taskno + 1)
total_ways_util = self.CountWaysUtil(mask, task_no + 1)
# now assign the tasks one by one to all possible persons and recursively assign for the remaining tasks.
if taskno in self.task:
for p in self.task[taskno]:
if task_no in self.task:
for p in self.task[task_no]:
# if p is already given a task
if mask & (1 << p):
continue
# assign this task to p and change the mask value. And recursively assign tasks with the new mask value.
total_ways_util += self.CountWaysUtil(mask | (1 << p), taskno + 1)
total_ways_util += self.CountWaysUtil(mask | (1 << p), task_no + 1)
# save the value.
self.dp[mask][taskno] = total_ways_util
self.dp[mask][task_no] = total_ways_util
return self.dp[mask][taskno]
return self.dp[mask][task_no]
def countNoOfWays(self, task_performed):