Advent of Code 2021: 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.
Calculate power consumption using binary diagnostic data. Part two finds oxygen and CO2 ratings using bit criteria.
python
#!/usr/bin/env python3
import numpy as np
import sys
with open(sys.argv[1]) as input:
lines = input.readlines()
lines = [list(line.strip()) for line in lines]
# Part 1
transposed = np.array(lines).T.tolist()
gamma_str = ''.join(['1' if col.count('1') > col.count('0') else '0' for col in transposed])
gamma = int(gamma_str, base = 2)
epsilon_str = ''.join(['0' if c == '1' else '1' for c in gamma_str])
epsilon = int(epsilon_str, base = 2)
print(gamma * epsilon)
# Part 2
def oxygen(lines, depth = 0):
if len(lines) == 1:
return int(''.join(lines[0]), base = 2)
transposed = np.array(lines).T.tolist()
most_common = '1' if transposed[depth].count('1') >= transposed[depth].count('0') else '0'
return oxygen([line for line in lines if line[depth] == most_common], depth + 1)
def co2(lines, depth = 0):
if len(lines) == 1:
return int(''.join(lines[0]), base = 2)
transposed = np.array(lines).T.tolist()
most_common = '1' if transposed[depth].count('1') < transposed[depth].count('0') else '0'
return co2([line for line in lines if line[depth] == most_common], depth + 1)
print(oxygen(lines) * co2(lines))