[Samba] define share without name

[Sampei]

With Samba 4.2.10 I wish to create one folder share so that Windows clients can access to it by typing only the IP address or netbios name of server, e.g. \\10.56.23.22 and the window will show immediately file list.
I read Samba doc and it’s necessary to define every share by symbol "[ section ]” but if I defined [test] share I woull access to it by typing \\ 10.56.23.22\test and this one it’s not my scope. Suggestions please?