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@JeffersGlass

JeffersGlass/day7.py Secret

Created Dec 8, 2020
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import sys
sys.path.append("..")
from usefulDecorators import *
#Creates a dictionary where keys are colors of bag (string) and the values are a set of the
#colors of bag which directly contain the key color
def createBagList():
bagList = dict()
with open('input.txt', 'r') as infile:
for line in infile:
#Split input line container colored and contained colors
container, contains = line.split(' bags contain ')
#This line is a hack that assumes all numbers are single digit, which they appear to be??
contains = [c.strip('\n. ').replace(' bags', '').replace(' bag', '')[2:] for c in contains.split(',') if 'no other bags' not in c]
#print(f"{container}\t\t{contains}")
for color in contains:
if color not in bagList:
bagList[color] = {container}
else:
bagList[color].add(container)
return bagList
def findParentColors(color, bagList):
if color not in bagList:
return set()
else:
retVal = bagList[color]
return retVal.union(*[findParentColors(c, bagList) for c in bagList[color]])
#Creates a dictionary of values where the keys are the container and the values are a list of colors that container can directly contain
#Note that this is essentially the opposite of what createBagList() does
def createContainedList():
baseList = dict()
with open('input.txt', 'r') as infile:
for line in infile:
container, contains = line.split(' bags contain ')
#This line is a hack that assumes all numbers are single digit, which they appear to be??
contains = [c.strip('\n. ').replace(' bags', '').replace(' bag', '') for c in contains.split(',') if 'no other bags' not in c]
contains = [(int(c[0]), c[2:]) for c in contains]
baseList[container] = contains
return baseList
def findTotalBags(color, bagList):
if color not in bagList:
raise ValueError(f"{color} is not in the list of keys of baglist")
else:
if len(bagList[color]) == 0: return 1
else: return sum([c[0] * findTotalBags(c[1], bagList) for c in bagList[color]]) + 1
if __name__ == '__main__':
#Solution to part 1
print(f"Solution to part 1: {len(findParentColors('shiny gold', createBagList()))}")
#Solution to part 2
print(f"Solution to part 2: {findTotalBags('shiny gold', createContainedList())-1}")
#Have to subtract 1 from the final answer, because findTotalBags includes itself in the results,
#which we want for every bag except the 'shiny gold' bag itself
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