static void Main(string[] args)
{
#region Parse input
string user = Console.ReadLine();
int Nconnections = int.Parse(Console.ReadLine());
for (int i = 0; i < Nconnections; i++)
{
string[] connection = Console.ReadLine().Split(' ');
string firstUser = connection[0];
string secondUser = connection[1];
if (users.ContainsKey(firstUser) && users.ContainsKey(secondUser))
{
users[firstUser].AddFriend(users[secondUser]);
users[secondUser].AddFriend(users[firstUser]);
}
else if (users.ContainsKey(firstUser))
{
User childUser = new User(secondUser);
users.Add(childUser.Value, childUser);
users[firstUser].AddFriend(users[secondUser]);
users[secondUser].AddFriend(users[firstUser]);
}
else if (users.ContainsKey(secondUser))
{
User parentUser = new User(firstUser);
users.Add(parentUser.Value, parentUser);
users[firstUser].AddFriend(users[secondUser]);
users[secondUser].AddFriend(users[firstUser]);
}
else
{
User childUser = new User(secondUser);
User parentUser = new User(firstUser);
users.Add(childUser.Value, childUser);
users.Add(parentUser.Value, parentUser);
users[firstUser].AddFriend(users[secondUser]);
users[secondUser].AddFriend(users[firstUser]);
}
}
searchedFriendsCount = int.Parse(Console.ReadLine());
results = new Queue<int>(searchedFriendsCount);
for (int i = 0; i < searchedFriendsCount; i++)
{
searchedFriends.Add(Console.ReadLine());
}
#endregion
for (int i = 0; i < searchedFriends.Count; i++)
{
if (!users.ContainsKey(user))
{
for (int j = 0; j < searchedFriends.Count; j++)
{
Console.WriteLine(-1);
}
return;
}
DFS(users[user], searchedFriends[i], 0);
if (results.Count > 0)
{
Console.WriteLine(results.Dequeue());
}
else
{
Console.WriteLine(-1);
}
visitedFriends.Clear();
}
}
/// <summary>
/// DFSs the specified users.
/// </summary>
/// <param name="users">The users.</param>
/// <param name="searchedFriends">The searched friends.</param>
private static void DFS(User user, string searchedFriend, int level)
{
Queue<Tuple<User, int>> queue = new Queue<Tuple<User, int>>();
queue.Enqueue(new Tuple<User, int>(user, 0));
visitedFriends.Add(user.Value);
while (queue.Count > 0)
{
var curentFriend = queue.Dequeue();
if (curentFriend.Item1.Value == searchedFriend)
{
results.Enqueue(curentFriend.Item2);
break;
}
foreach (var friend in curentFriend.Item1.Friends)
{
if (!visitedFriends.Contains(friend.Value))
{
queue.Enqueue(new Tuple<User, int>(friend, curentFriend.Item2 + 1));
visitedFriends.Add(friend.Value);
}
}
}
}
public void AddFriend(User child)
{
friends.Add(child);
}
