def findShortest(graph_nodes, graph_from, graph_to, ids, val):
    graph = defaultdict(set)
    for start, end in zip(graph_from, graph_to):
        graph[start].add(end)
        graph[end].add(start)
    
    min_path_len = math.inf
    for node, node_color in enumerate(ids, start=1):
        if node_color != val:
            continue
        visited = set([node])
        queue = deque(graph[node])
        curr_path_len = 0
        found_at = None
        while queue:
            curr = queue.popleft()
            if curr in visited:
                continue
            visited.add(curr)
            curr_path_len += 1
            curr_color = ids[curr-1]
            if curr_color == node_color:
                found_at = curr_path_len
                break
            queue.extend(graph[curr])
        if found_at:
            min_path_len = min(min_path_len, found_at)
    if min_path_len == math.inf:
        return -1
    return min_path_len