advent_of_code_2024/02_solution.py

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
Created on Mon Dec  2 18:25:45 2024

@author: bernie
"""
def solve_part_1(inpt):
    diff_lines = [[int(nr1) - int(nr2) for nr1, nr2 in zip(line, line[1:])] for line in inpt]
    no_safe_reports = sum(
        all(nr >= 1 and nr <= 3 for nr in line) or
        all(nr <= -1 and nr >= -3 for nr in line)
        for line in diff_lines)
    print(f"safe reports (part 1): {no_safe_reports}")


def _is_report_safe(line):
    all_in_range = all(nr1 != nr2 and abs(nr1 - nr2) <= 3 for nr1, nr2 in zip(line, line[1:]))
    all_increasing = all(nr1 > nr2 for nr1, nr2 in zip(line, line[1:]))
    all_decreasing = all(nr1 < nr2 for nr1, nr2 in zip(line, line[1:]))
    return all_in_range and (all_increasing or all_decreasing)


def solve_part_2(inpt):
    inpt = [[int(nr) for nr in line] for line in inpt]
    no_safe_reports = 0
    for line in inpt:
        if _is_report_safe(line):
            no_safe_reports += 1
            continue

        for idx_to_rm in range(len(line)):
            modified_line = line[:idx_to_rm] + line[idx_to_rm+1:]
            if _is_report_safe(modified_line):
                no_safe_reports += 1
                break

    print(f"safe reports (part 2): {no_safe_reports}")


if __name__ == "__main__":
    with open("02_input.txt", "r") as inpt_file:
        inpt = [line.split(" ") for line in inpt_file.readlines()]

    solve_part_1(inpt)
    solve_part_2(inpt)