int ans = 0;
    public int maximumInvitations(int[] favorite) {
        List<List<Integer>> graph = new ArrayList<>();
        int n = favorite.length;
        for (int i = 0; i <= n; i++) {
            graph.add(new ArrayList<>());
        }
        for (int i = 0; i < n; i++) {
            int index = i + 1;
            graph.get(index).add(favorite[i]);
            graph.get(favorite[i]).add(index);
        }
        ans = 0;
        HashSet<Integer> visited = new HashSet<>();
        for (int i = 1; i <= n; i++) {
            if (!visited.contains(i))
                dfs(i, graph, visited, 1);
        }
        return ans;
    }

    private void dfs(int i, List<List<Integer>> graph, HashSet<Integer> visited, int count) {
        visited.add(i);
        ans = Math.max(ans, count);
        for (int u : graph.get(i)) {
            if (!visited.contains(u)) {
                dfs(u, graph, visited, count + 1);
            }
        }
    }