return term[0]
def part1_regex(input):
# Alternative approach with regexes
# works well for part 1 but hard to expand for part 2
gr = input.get_groups()
rules = gr[0]
messages = gr[1]
rule0 = make_rule0_regex_for_pt1(rules)
r = re.compile(f"^{rule0}$")
valid = [msg for msg in messages if r.match(msg)]
return len(valid)
e.run_tests(1, part1_regex)
e.run_main(1, part1_regex)
def replace_rules_for_pt2(nonterm):
nonterm[8] = [[42], [42, 8]]
nonterm[11] = [[42, 31], [42, 11, 31]]
def msg_valid(msg, term, nonterm):
q = deque()
q.append((0, [0]))
while q:
index, rules = q.popleft()
rule = rules[0]
if rule in term:
-2""", 0, None)
e.T("""-1
-2
-3""", -6, None)
e.T("""+1
-2
+3
+1""", None, 2)
def part1(input):
ints = [int(x) for x in input.get_valid_lines()]
return sum(ints)
e.run_tests(1, part1)
e.run_main(1, part1)
def part2(input):
ints = [int(x) for x in input.get_valid_lines()]
c = 0
s = set()
while True:
for x in ints:
c += x
if c in s:
return c
s.add(c)
def loop(start, loops):
v = 1
for _ in range(loops):
v = (v * start) % 20201227
return v
def part1(input):
ln = input.get_valid_lines()
A = int(ln[0])
B = int(ln[1])
# A = 7 ** n mod 20201227
# B = 7 ** m mod 20201227
# 20201227 is prime
n = get_loop_number(A)
m = get_loop_number(B)
print(f"Loop numbers: {n}, {m}")
return loop(A, m)
e.run_tests(1, part1)
e.run_main(1, part1)
def part2(input):
pass
# e.run_tests(2, part2)
# e.run_main(2, part2)