intersections = [(x, y) for (x, y) in scaffold if
(all(neighbour in scaffold for neighbour in [(x+1, y), (x-1, y), (x, y+1), (x, y-1)]))]
return sum([(x * y) for (x, y) in intersections])
def part2():
program = Program("17")
program.program[0] = 2
main = "A,B,A,B,C,B,C,A,B,C\n"
a = "R,4,R,10,R,8,R,4\n"
b = "R,10,R,6,R,4\n"
c = "R,4,L,12,R,6,L,12\n"
camera = "n\n"
input_buffer = []
[input_buffer.extend(ord(c) for c in routine) for routine in [main, a, b, c, camera]]
program.run(input_buffer)
return program.output_buffer[-1]
if __name__ == "__main__":
part1_correct = 5788
part2_correct = 648545
print_answer(1, part1(), part1_correct)
print_answer(2, part2(), part2_correct)
if moons == moons_initial and velocities == velocities_initial:
return steps
def part1(moons, velocities):
for _ in range(1000):
apply_gravity(moons, velocities)
apply_velocity(moons, velocities)
total_energy = calc_energy(moons, velocities)
return total_energy
def part2(moons, velocities):
return reduce(lcm,
[get_period(moons, velocities, dim) for dim in range(3)])
if __name__ == "__main__":
part1_correct = 12082
part2_correct = 295693702908636
moons = [extract_ints(moon) for moon in get_input("12")]
velocities = [[0 for _ in ["x", "y", "z"]] for moon in moons]
print_answer(1, part1(copy.deepcopy(moons), copy.deepcopy(velocities)),
part1_correct)
print_answer(2, part2(copy.deepcopy(moons), copy.deepcopy(velocities)),
part2_correct)
def part2(program):
for noun in range(99):
for verb in range(99):
# Reset program to initial state
program.reset()
# "the value placed in address 1 is called the noun"
program.program[1] = noun
# "the value placed in address 2 is called the verb"
program.program[2] = verb
program.run()
# find noun and verb that cause program to output 19690720
if program.program[0] == 19690720:
# return 100 * noun + verb
return 100 * noun + verb
if __name__ == "__main__":
part1_correct = 4945026
part2_correct = 5296
program = Program(2)
print_answer(1, part1(program), part1_correct)
print_answer(2, part2(program), part2_correct)
if position in portal_locations['ZZ'] and q_level == 0:
# queue is sorted by distance, first route to exit is shortest
return q_distance + 1
if position in walkable - seen:
heappush(q, (q_distance + 1, q_level, position))
def part1(portal_names, portal_locations, walkable):
return get_shortest_route(portal_names, portal_locations, walkable)
def part2(portal_names, portal_locations, walkable, portal_sides):
return get_shortest_route(portal_names, portal_locations, walkable, portal_sides)
if __name__ == "__main__":
part1_correct = 596
part2_correct = 7610
maze = get_input(20, strip=False)
portal_names, portal_locations, portal_sides = find_portals(maze)
walkable = get_walkable(maze)
print_answer(1, part1(portal_names, portal_locations,
walkable), part1_correct)
print_answer(2, part2(portal_names, portal_locations,
walkable, portal_sides), part2_correct)
