def problem_5():
""" Attempt to solve the problem... """
answer = lcm(1, 2)
# We can just continue to recalculate the lcm for each new number in the
# list because: lcm(a,b,c) = lcm(a,lcm(b,c))
for number in xrange(2, 20+1):
print number
answer = lcm(number, answer)
return answer
def count(self, name, value, split):
value = self.validate(value)
file_groups = file_scanner(config.file_in_path)
file_group = file_groups[self.type][value]
file_path_name, skip_records_name, count_records_name = name.split(':')
if len(file_group.files) == split:
return split
elif len(file_group.files) >= split:
return len(file_group.files)
else:
return lcm(split, len(file_group.files))
def Part2(lines):
moons = readMoons(lines)
previousStates = [{} for axis in range(3)]
foundRepeat = [False for axis in range(3)]
i = 1
while True:
applyGravity(moons)
applyVelocity(moons)
moonIdx = 0
for axis in range(3):
if 0 == reduce(
operator.add,
[abs(vel[axis]) for vel in [moon[1] for moon in moons]]):
foundRepeat[axis] = i
i += 1
if reduce(lambda x, y: bool(x) and bool(y), foundRepeat):
break
lcm = com.lcm(foundRepeat)
print(
'Took ', lcm, ' iterations or maybe ', lcm * 2
) # not sure why I have to multiply by 2 sometimes but it works on the tests
states = set()
initial_state = tuple(moon.state() for moon in moons)
steps = 0
def get_state_of_axis(state, axis):
return tuple((moon[axis], moon[axis + 3]) for moon in state)
cycles = {}
while len(cycles) < 3:
# gravity
for m1, m2 in combinations(moons, 2):
for i in range(3):
if m1.pos[i] < m2.pos[i]:
m1.vel[i] += 1
m2.vel[i] -= 1
elif m1.pos[i] > m2.pos[i]:
m1.vel[i] -= 1
m2.vel[i] += 1
# velocity
for moon in moons:
moon.pos = tadd(moon.pos, moon.vel)
steps += 1
current_state = tuple(moon.state() for moon in moons)
for i in range(3):
if get_state_of_axis(current_state, i) == get_state_of_axis(initial_state, i):
if i not in cycles:
cycles[i] = steps
print(lcm(lcm(cycles[0], cycles[1]), cycles[2]))
def test_lcm():
"""Tests covering the lcm function"""
assert lcm(12, 30) == 60
assert lcm(24, 300) == 600
def run():
nums = (x for x in xrange(1,21))
return lcm(*nums)
