Advent of Code 2022: Day 3
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Refer to the previous post about AoC, and to the git repository with my solutions in Python 3.
Link to Day #3 puzzle.
Find misplaced items in rucksacks. Part two finds common items across three rucksacks.
python
#!/usr/bin/env python3
import sys
def priority(item):
if item.islower():
return ord(item) - ord('a') + 1
else:
assert item.isupper()
return ord(item) - ord('A') + 27
def main():
with open(sys.argv[1]) as input:
lines = input.read().splitlines()
total_priority = 0
# Part 1
for line in lines:
c1 = line[:len(line)//2]
c2 = line[len(line)//2:]
item = next(iter(set(c1).intersection(c2)))
total_priority += priority(item)
print(total_priority)
# Part 2
print(sum([priority(next(iter(set(line1).intersection(line2).intersection(line3))))
for (line1, line2, line3) in zip(lines[::3], lines[1::3], lines[2::3])]))
if __name__ == '__main__':
main()