def test_2b():
bodies = [
Body(Point3(-8,-10, 0)),
Body(Point3( 5, 5,10)),
Body(Point3( 2, -7, 3)),
Body(Point3( 9, -8,-3)),
]
assert until_repeat_steps(bodies) == 4686774924
print("passed test_2b")
def part_2():
bodies = [
Body(Point3(-1, -4, 0)),
Body(Point3(4, 7, -1)),
Body(Point3(-14, -10, 9)),
Body(Point3(1, 2, 17)),
]
ss = until_repeat_steps(bodies, debug=True)
print(f"part 2: simulation will repeat after {ss} steps")
def test_2a():
bodies = [
Body(Point3(-1, 0, 2)),
Body(Point3(2, -10, -7)),
Body(Point3(4, -8, 8)),
Body(Point3(3, 5, -1))
]
assert until_repeat_steps(bodies) == 2772
print("passed test_2a")
def part_1(steps=1000):
bodies = [
Body(Point3(-1, -4, 0)),
Body(Point3(4, 7, -1)),
Body(Point3(-14, -10, 9)),
Body(Point3(1, 2, 17)),
]
last(simulate(bodies, steps_limit=steps))
total_energy = sum(b.energy for b in bodies)
print(f"part 1: total energy after {steps} steps is {total_energy}")
def test_reverse():
bodies = [
Body(Point3(-1, 0, 2)),
Body(Point3(2, -10, -7)),
Body(Point3(4, -8, 8)),
Body(Point3(3, 5, -1))
]
states_f = list(simulate(bodies, steps_limit=2772))
states_b = list(simulate_reverse(bodies, steps_limit=2772))
assert len(states_f) == len(states_b) == 2773
assert states_f[0] == states_b[0]
assert states_f[0] == states_f[-1]
assert states_b[0] == states_b[-1]
assert states_f[1] == states_b[-2]
assert states_f[2] == states_b[-3]
assert states_f[1000] == states_b[-1001]
print("passed test_reverse")
def test_1b():
bodies = [
Body(Point3(-8,-10, 0)),
Body(Point3( 5, 5,10)),
Body(Point3( 2, -7, 3)),
Body(Point3( 9, -8,-3)),
]
last_state = last(simulate(bodies, steps_limit=100))
assert last_state == (
(Point3( 8, -12, -9), Vector3(-7, 3, 0)),
(Point3( 13, 16, -3), Vector3( 3, -11, -5)),
(Point3(-29, -11, -1), Vector3(-3, 7, 4)),
(Point3( 16, -13, 23), Vector3( 7, 1, 1)),
)
assert sum(b.energy for b in bodies) == 1940
print("passed test_1b")
def from_str(cls, line: str) -> 'Particle':
# 'p=<-201,-1266,-2683>, v=<-29,-181,-382>, a=<2,13,31>'
vals = [int(val) for val in parse_line(line.strip(), "p=<$,$,$>, v=<$,$,$>, a=<$,$,$>")]
assert len(vals) == 9
return cls(pos=Point3(*vals[:3]), vel=Vector3(*vals[3:6]), acc=Vector3(*vals[6:]))
def only_z(self):
return Body(Point3(0, 0, self.pos.z), Vector3(0, 0, self.vel.z))
def only_y(self):
return Body(Point3(0, self.pos.y, 0), Vector3(0, self.vel.y, 0))
def only_x(self):
return Body(Point3(self.pos.x, 0, 0), Vector3(self.vel.x, 0, 0))
def test_1a():
bodies = [
Body(Point3(-1, 0, 2)),
Body(Point3(2, -10, -7)),
Body(Point3(4, -8, 8)),
Body(Point3(3, 5, -1))
]
r = list(simulate(bodies, steps_limit=10))
assert len(r) == 11
assert r[1] == (
(Point3( 2, -1, 1), Vector3( 3, -1, -1)),
(Point3( 3, -7, -4), Vector3( 1, 3, 3)),
(Point3( 1, -7, 5), Vector3(-3, 1, -3)),
(Point3( 2, 2, 0), Vector3(-1, -3, 1)),
)
assert r[2] == (
(Point3( 5, -3, -1), Vector3( 3, -2, -2)),
(Point3( 1, -2, 2), Vector3(-2, 5, 6)),
(Point3( 1, -4, -1), Vector3( 0, 3, -6)),
(Point3( 1, -4, 2), Vector3(-1, -6, 2)),
)
assert r[3] == (
(Point3( 5, -6, -1), Vector3( 0, -3, 0)),
(Point3( 0, 0, 6), Vector3(-1, 2, 4)),
(Point3( 2, 1, -5), Vector3( 1, 5, -4)),
(Point3( 1, -8, 2), Vector3( 0, -4, 0)),
)
assert r[4] == (
(Point3( 2, -8, 0), Vector3(-3, -2, 1)),
(Point3( 2, 1, 7), Vector3( 2, 1, 1)),
(Point3( 2, 3, -6), Vector3( 0, 2, -1)),
(Point3( 2, -9, 1), Vector3( 1, -1, -1)),
)
assert r[5] == (
(Point3(-1, -9, 2), Vector3(-3, -1, 2)),
(Point3( 4, 1, 5), Vector3( 2, 0, -2)),
(Point3( 2, 2, -4), Vector3( 0, -1, 2)),
(Point3( 3, -7, -1), Vector3( 1, 2, -2)),
)
assert r[6] == (
(Point3(-1, -7, 3), Vector3( 0, 2, 1)),
(Point3( 3, 0, 0), Vector3(-1, -1, -5)),
(Point3( 3, -2, 1), Vector3( 1, -4, 5)),
(Point3( 3, -4, -2), Vector3( 0, 3, -1)),
)
assert r[7] == (
(Point3( 2, -2, 1), Vector3( 3, 5, -2)),
(Point3( 1, -4, -4), Vector3(-2, -4, -4)),
(Point3( 3, -7, 5), Vector3( 0, -5, 4)),
(Point3( 2, 0, 0), Vector3(-1, 4, 2)),
)
assert r[8] == (
(Point3( 5, 2, -2), Vector3( 3, 4, -3)),
(Point3( 2, -7, -5), Vector3( 1, -3, -1)),
(Point3( 0, -9, 6), Vector3(-3, -2, 1)),
(Point3( 1, 1, 3), Vector3(-1, 1, 3)),
)
assert r[9] == (
(Point3( 5, 3, -4), Vector3( 0, 1, -2)),
(Point3( 2, -9, -3), Vector3( 0, -2, 2)),
(Point3( 0, -8, 4), Vector3( 0, 1, -2)),
(Point3( 1, 1, 5), Vector3( 0, 0, 2)),
)
assert r[10] == (
(Point3( 2, 1, -3), Vector3(-3, -2, 1)),
(Point3( 1, -8, 0), Vector3(-1, 1, 3)),
(Point3( 3, -6, 1), Vector3( 3, 2, -3)),
(Point3( 2, 0, 4), Vector3( 1, -1, -1)),
)
assert sum(b.energy for b in bodies) == 179
print("passed test_1a")