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psf/black code formatting (#1277)

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This commit is contained in:
William Zhang
2019-10-05 01:14:13 -04:00
committed by Christian Clauss
parent 07f04a2e55
commit 9eac17a408
291 changed files with 6014 additions and 4571 deletions
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53
dynamic_programming/bitmask.py
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@@ -13,54 +13,55 @@ from collections import defaultdict
class AssignmentUsingBitmask:
def __init__(self,task_performed,total):
def __init__(self, task_performed, total):
self.total_tasks = total #total no of tasks (N)
self.total_tasks = total # total no of tasks (N)
# DP table will have a dimension of (2^M)*N
# initially all values are set to -1
self.dp = [[-1 for i in range(total+1)] for j in range(2**len(task_performed))]
self.dp = [
[-1 for i in range(total + 1)] for j in range(2 ** len(task_performed))
]
self.task = defaultdict(list) #stores the list of persons for each task
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
# finalmask is used to check if all persons are included by setting all bits to 1
self.finalmask = (1 << len(task_performed)) - 1
def CountWaysUtil(self,mask,taskno):
def CountWaysUtil(self, mask, taskno):
# if mask == self.finalmask all persons are distributed tasks, return 1
if mask == self.finalmask:
return 1
#if not everyone gets the task and no more tasks are available, return 0
# if not everyone gets the task and no more tasks are available, return 0
if taskno > self.total_tasks:
return 0
#if case already considered
if self.dp[mask][taskno]!=-1:
# if case already considered
if self.dp[mask][taskno] != -1:
return self.dp[mask][taskno]
# Number of ways when we dont this task in the arrangement
total_ways_util = self.CountWaysUtil(mask,taskno+1)
total_ways_util = self.CountWaysUtil(mask, taskno + 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 p is already given a task
if mask & (1<<p):
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), taskno + 1)
# save the value.
self.dp[mask][taskno] = total_ways_util
return self.dp[mask][taskno]
def countNoOfWays(self,task_performed):
def countNoOfWays(self, task_performed):
# Store the list of persons for each task
for i in range(len(task_performed)):
@@ -68,22 +69,22 @@ class AssignmentUsingBitmask:
self.task[j].append(i)
# call the function to fill the DP table, final answer is stored in dp[0][1]
return self.CountWaysUtil(0,1)
return self.CountWaysUtil(0, 1)
if __name__ == '__main__':
if __name__ == "__main__":
total_tasks = 5 #total no of tasks (the value of N)
total_tasks = 5 # total no of tasks (the value of N)
#the list of tasks that can be done by M persons.
task_performed = [
[ 1 , 3 , 4 ],
[ 1 , 2 , 5 ],
[ 3 , 4 ]
]
print(AssignmentUsingBitmask(task_performed,total_tasks).countNoOfWays(task_performed))
# the list of tasks that can be done by M persons.
task_performed = [[1, 3, 4], [1, 2, 5], [3, 4]]
print(
AssignmentUsingBitmask(task_performed, total_tasks).countNoOfWays(
task_performed
)
)
"""
For the particular example the tasks can be distributed as
(1,2,3), (1,2,4), (1,5,3), (1,5,4), (3,1,4), (3,2,4), (3,5,4), (4,1,3), (4,2,3), (4,5,3)
total 10
"""
"""