day_01.py

with open('./inputs/01.txt', 'r') as infile:
    directions = infile.readline().split(', ')

ROTATION = {
    'L': 1j,
    'R': -1j
}

current_direction = 1j
location = 0+0j

visited_locations = set()
passed_twice = False


def find_manhattan(loc):
    return int(abs(loc.real) + abs(loc.imag))


for instruction in directions:
    rot, dist = instruction[0], int(instruction[1:])
    current_direction *= ROTATION[rot]

    for _ in range(dist):
        location += current_direction
        if not passed_twice and location in visited_locations:
            print("This looks familiar! "
                  f"I must have been at {location} before!")
            print("The distance from the start is:", find_manhattan(location))
            passed_twice = True
        else:
            visited_locations.add(location)

print('....')
print("Ok, I've come to the end of your instructions and I'm at:", location)
print(f"That's {find_manhattan(location)} blocks away from the the start.")