After you finished the simple task, Mr. Ye give you a new task. Every zstu acmer knows bbs.zjchess.com. But do you know how many tasks the users on bbs.zjchess.com finish every day? Supposed that there are 4 web pages on bbs.zjchess.com,p1,p2,p3,p4. And we can read from the log file: p1 - 10.17.12.21 p2 p1 10.17.12.21 p3 p2 10.17.12.21 p4 p3 10.17.12.21 p1 - 10.17.12.21 p2 p1 10.17.12.21 p3 p2 10.17.12.21 p4 p3 10.17.12.21 p1 - 10.17.12.21 p4 p1 10.17.12.21 p1 - 10.17.12.21 p2 p3 10.10.10.1 p2 p1 10.17.12.21 p1 - 10.11.16.23 p4 p2 10.10.10.1 p4 p1 10.11.16.23 We can see there are 3 tasks finished by the user who comes from 10.17.12.21: (1) -(begin) -> p1 -> p2 -> p3 -> p4 -(begin) -> p1 -> p2 -> p3 -> p4 (same as before) (2) -(begin) -> p1 -> p4 (3) -(begin) -> p1 -> p2 1 tasks finished by the user who comes from 10.10.10.1: (1) p3 -> p2 -> p4 1 tasks finished by the user who comes from 10.11.16.23: (1) -(begin) -> p1 -> p4 So we say there are 5 tasks(3+1+1) finished by all the users.

The input file contains several test cases. Each test cases starts one integer number n (n <= 100), then n lines ffollows. Each line has 3 parts: destination page ,source page and ip.(pages no more than 50,p1,p2...p50, "-" is a blank page.)

For each test case output on a single line the number of tasks.

if one ip view the pages in the order:

p2 p1         p1 -> p2
p3 p2         p2 -> p3  one task finished,
p3 p1         p1 -> p3  new task begin, because the beginning page p1 is not the page p3

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