function hanoi(posts) {
    // Write your code here
    const n = posts.length;
    const rods = [0, 0, 0, 0];
    for (let i = 0; i < n; i++) {
        rods[posts[i] - 1] += 2 ** i;
    }
    const base = 2 ** n;
    const win_state = (base - 1) * (base ** 3);
    const start_state =
        rods[0] * (base ** 3) + rods[1] * (base ** 2) + rods[2] * base + rods[3];
    const visited = new Set();
    let current = [start_state];
    let moves = 0;

    while (current.length > 0) {
        const next = [];

        for (const state of current) {
            if (state === win_state) {
                return moves;
            }
            if (visited.has(state)) {
                continue;
            }
            visited.add(state);
            const rods = [
                Math.floor((state / (base ** 3)) % base),
                Math.floor((state / (base ** 2)) % base),
                Math.floor((state / base) % base),
                state % base
            ];
            const top_discs = rods.map(n =>
                n === 0 ? Infinity : n ^ (n & (n - 1))
            );

            for (let i = 0; i < 4; i++) {
                for (let j = i + 1; j < 4; j++) {
                    if (top_discs[i] === Infinity && top_discs[j] === Infinity) {
                        continue;
                    }
                    let new_state;
                    if (top_discs[i] < top_discs[j]) {
                        new_state =
                            state -
                            top_discs[i] * (base ** (3 - i)) +
                            top_discs[i] * (base ** (3 - j));
                    } else {
                        new_state =
                            state +
                            top_discs[j] * (base ** (3 - i)) -
                            top_discs[j] * (base ** (3 - j));
                    }
                    if (!visited.has(new_state)) {
                        next.push(new_state);
                    }
                }
            }
        }
        moves += 1;
        current = next;
    }
}