day2.py

from utils import parse_file_to_int_list

# --- Day 2: Red-Nosed Reports ---


def decreasing(lst):
    return all(
        (current > next_elem) and (1 <= (current - next_elem) <= 3)
        for current, next_elem in zip(lst, lst[1:])
    ) if len(lst) > 1 else True

def increasing(lst):
    return all(
        (current < next_elem) and (1 <= abs(current - next_elem) <= 3)
        for current, next_elem in zip(lst, lst[1:])
    ) if len(lst) > 1 else True

def reports():
    all_lst = parse_file_to_int_list('./input/day2.txt')
    count = sum(map(lambda x: 1 if decreasing(x) or increasing(x) else 0, all_lst))
    return count

print('part1', reports())

def reports2():
    all_lst = parse_file_to_int_list('./input/day2.txt')
    count = 0

    for lst in all_lst:
        if decreasing(lst) or increasing(lst):
            count += 1
        else:
            for i in range(len(lst)):
                removed_lst = lst[:i] + lst[i+1:]
                if decreasing(removed_lst) or increasing(removed_lst):
                    count += 1
                    break

    return count

print('part2', reports2())