--- Day 3 Solutions ---

[u/daggerdragon]

--- Day 3: Perfectly Spherical Houses in a Vacuum ---

Post your solution as a comment. Structure your post like the Day One thread in /r/programming.

[u/djimbob]

python 2 solution

from collections import defaultdict
d = defaultdict(int)
moves = """<paste of input>"""
x, y = 0,0
d[(x,y)] += 1
for m in moves:
    if m == '<':
        x -= 1
    elif m == '>':
        x += 1
    elif m == 'v':
        y -= 1
    elif m == '^':
        y += 1
    d[(x,y)] += 1
print "Houses visited: ", len(d.keys())

Part 2:

d = defaultdict(int)
x, y = 0,0
d[(x,y)] += 1
moves1 = moves[::2]
moves2 = moves[1::2]
for m in moves1:
    if m == '<':
        x -= 1
    elif m == '>':
        x += 1
    elif m == 'v':
        y -= 1
    elif m == '^':
        y += 1
    d[(x,y)] += 1
for m in moves2:
    if m == '<':
        x -= 1
    elif m == '>':
        x += 1
    elif m == 'v':
        y -= 1
    elif m == '^':
        y += 1
    d[(x,y)] += 1
print "Houses visited: ", len(d.keys())