Advent of Code Day 12 (Part 1)

AoC2020_day12_p1.py

COMPASS = {
    "E": (+1, 0), 
    "S": (0, +1),
    "W": (-1, 0),
    "N": (0, -1)
}

ship_pos = [0, 0]
ship_heading = 0

nav_list = [(n[0], int(n[1:])) for n in open("input_12")]

for nav, value in nav_list:
    if nav in ("R", "L"):
        if nav == "L":
            value = -value
        ship_heading = (ship_heading+value)%360

    if nav == "F":
        nav = "ESNW"[ship_heading//90]

    if nav in COMPASS.keys():
        ship_pos[0] += COMPASS[nav][0] * value
        ship_pos[1] += COMPASS[nav][1] * value

print(abs(ship_pos[0]) + abs(ship_pos[1]))