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def read_input():
# Read in an input file containing ones and zeros on each line.
with open('./input/3_1.txt') as f:
input = f.readlines()
# Convert each line to a list of integers.
input = [list(map(int, line.strip())) for line in input]
return input
def calculate_most_common_number(input, i):
# For each list in the input list, get element i
subset = [row[i] for row in input]
# If there is an equal number of 0's and 1's, return 1.
if subset.count(0) == subset.count(1):
return 1
# Get the most common number in the subset.
most_common_number = max(set(subset), key=subset.count)
return most_common_number
def filter_list_based_on_most_common_number(input, i):
# Calculate the most common number at position i in each list in input.
most_common_number = calculate_most_common_number(input, i)
# Filter out all lists that do not contain the most common number at position i.
filtered_list = [row for row in input if row[i] == most_common_number]
return filtered_list
def get_unique_based_on_most_common_filtering(input):
# Get the unique number based on the most common number filtering.
unique_number = 0
for i in range(len(input[0])):
filtered_list = filter_list_based_on_most_common_number(input, i)
# put the filtered list back in the input variable.
input = filtered_list
# if length of filtered list is 1, then the unique number is the number at position i in the filtered list.
if len(filtered_list) == 1:
# convert the list of ones and zeros to string and then to an binary integer.
unique_number += int(''.join(map(str, filtered_list[0])), 2)
# break
break
return unique_number
def calculate_least_common_number(input, i):
# For each list in the input list, get element i
subset = [row[i] for row in input]
# If there is an equal number of 0's and 1's, return 1.
if subset.count(0) == subset.count(1):
return 0
# Get the least common number in the subset.
least_common_number = min(set(subset), key=subset.count)
return least_common_number
def filter_list_based_on_least_common_number(input, i):
# Calculate the least common number at position i in each list in input.
least_common_number = calculate_least_common_number(input, i)
# Filter out all lists that do not contain the least common number at position i.
filtered_list = [row for row in input if row[i] == least_common_number]
return filtered_list
def get_unique_based_on_least_common_filtering(input):
# Get the unique number based on the least common number filtering.
unique_number = 0
for i in range(len(input[0])):
filtered_list = filter_list_based_on_least_common_number(input, i)
# put the filtered list back in the input variable.
input = filtered_list
# if length of filtered list is 1, then the unique number is the number at position i in the filtered list.
if len(filtered_list) == 1:
# convert the list of ones and zeros to string and then to an binary integer.
unique_number += int(''.join(map(str, filtered_list[0])), 2)
# break
break
return unique_number
def main():
# calculate both the unique numbers based on most common and least common filtering.
input = read_input()
unique_number_most_common = get_unique_based_on_most_common_filtering(input)
unique_number_least_common = get_unique_based_on_least_common_filtering(input)
print('The unique number based on most common filtering is: {}'.format(unique_number_most_common))
print('The unique number based on least common filtering is: {}'.format(unique_number_least_common))
# Multiply them together and print the result.
print('The product of the two unique numbers is: {}'.format(unique_number_most_common * unique_number_least_common))
if __name__ == '__main__':
main()
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