advent-of-code/2019/d04/ex2/ex2.py

36 lines
826 B
Python
Executable file

#!/usr/bin/env python
from typing import Iterator
def is_valid_password(p: int) -> bool:
digits = str(p)
def has_unique_adjacent_digit():
counts = {d: 0 for d in range(10)}
for (a, b) in zip(digits, digits[1:]):
if a == b:
counts[int(a)] += 1
return any(count == 1 for count in counts.values())
def digits_never_decrease():
return all(a == b for a, b in zip(sorted(digits), digits))
return has_unique_adjacent_digit() and digits_never_decrease()
def compute_pass(begin: int, end: int) -> Iterator[int]:
for p in range(begin, end + 1):
if is_valid_password(p):
yield p
def main() -> None:
begin = 264793
end = 803935
print(sum(1 for p in compute_pass(begin, end)))
if __name__ == "__main__":
main()