Goal
Calculate how many separate groups of people there are in an organisation based on lists of users in email threads.
A group consists of people who have email threads in common up to any degree of separation - e.g. if Group 1 and 2 are separate and person A in Group 1 sends an email to person B in Group 2, the groups become one and include everyone from Group 1 and Group 2.
So two groups are separate if no member of either group has ever appeared in an email thread with anyone from the other group.
Input
Line 1: An integer N with the number of email threads.
Next N lines: A list of space separated strings representing the unique list of p participants in an email thread. Each value represents a (hashed) user's email address.
Output
Line 1 : The number g of separate groups of users.
Constraints
5 ≤ N ≤ 500
2 ≤ p ≤ 16
1 ≤ g ≤ 500
Example
Input
5
oDQW ddfx
ddfx nxPS
gkyz cpOV
qrAB ddfx
ktCJ ddfx
