import lib

EXAMPLE = """
LLR

AAA = (BBB, BBB)
BBB = (AAA, ZZZ)
ZZZ = (ZZZ, ZZZ)
"""

EXAMPLE2 = """
LR

11A = (11B, XXX)
11B = (XXX, 11Z)
11Z = (11B, XXX)
22A = (22B, XXX)
22B = (22C, 22C)
22C = (22Z, 22Z)
22Z = (22B, 22B)
XXX = (XXX, XXX)
"""

def solve(lines: list[str]):
    res = 0
    elems = {}
    for (i, line) in enumerate(lines):
        if i == 0:
            first = list(line)
        else:
            left, pair = line.split("=")
            left = left.strip()
            pair = pair.replace("(", "").replace(")", "").strip().split(", ")
            elems[left] = pair
    i = 0
    start = "AAA"
    while start != "ZZZ":
        dir = first[i % len(first)]
        if dir == "L":
            start = elems[start][0]
        elif dir == "R":
            start = elems[start][1]
        else:
            raise Exception("Unex")
        i += 1

    return i

def solve2(lines: list[str]):
    res = 0
    elems = {}
    starts = []
    ends = {}
    for (i, line) in enumerate(lines):
        if i == 0:
            first = list(line)
        else:
            left, pair = line.split("=")
            left = left.strip()
            if left.endswith("A"):
                starts.append(left)
            if left.endswith("Z"):
                ends[left] = 0
            pair = pair.replace("(", "").replace(")", "").strip().split(", ")
            elems[left] = pair
    i = 0
    while True:
        new_starts = []
        for start in starts:
            dir = first[i % len(first)]
            if dir == "L":
                new_starts.append(elems[start][0])
            elif dir == "R":
                new_starts.append(elems[start][1])
            else:
                raise Exception("Unex")
        i += 1
        for start in new_starts:
            if start in ends and ends[start] == 0:
                ends[start] = i
        starts = new_starts

        for e in ends.values():
            if e == 0:
                break
        else:
            break
    # 25:00
    return lib.lcm(ends.values())

def main():
    lines = lib.str_to_lines_no_empty(EXAMPLE)
    print("Example  1:", solve(lines))

    lines = lib.str_to_lines_no_empty(open("i8.txt").read())
    print("Solution 1:", solve(lines))

    lines = lib.str_to_lines_no_empty(EXAMPLE2)
    print("Example  2:", solve2(lines))

    lines = lib.str_to_lines_no_empty(open("i8.txt").read())
    print("Solution 2:", solve2(lines))

if __name__ == "__main__":
    main()