advent3.py

advent3.py

#!/usr/bin/env python3

import sys

MOVES = {
    ">": ( 1,  0),
    "<": (-1,  0),
    "^": ( 0,  1),
    "v": ( 0, -1),
}

def houses(steps):
    x = 0
    y = 0

    for step in steps:
        dx, dy = MOVES[step]
        x += dx
        y += dy
        yield (x, y)

data = sys.stdin.readlines()[0].strip()

santa = set(houses(data[0::2]))
robo = set(houses(data[1::2]))
unique = len(santa | robo)

print(unique)