400789: GYM100247 K Three Contests

Three contests have finished at the programming training camp. Now every team considers itself stronger than every other team which has been beaten by it at least at the one of these contests.

How many pairs of teams, where each team considers itself stronger than the other, exist?

The first line contains the only integer n (1 ≤ n ≤ 200000) — the number of teams at the training camp.

Each of the next n lines contains three integers: a_i, b_i and c_i (1 ≤ a_i, b_i, c_i ≤ n) — the places taken by team i at the first, the second and the third contest correspondingly.

It's guaranteed that there is no contest where some teams share the same place, that is, all a_i are distinct, all b_i are distinct, and all c_i are distinct.

Output the only integer — number of pairs of teams where each team considers itself stronger than the other.

4
1 3 1
2 2 4
4 1 2
3 4 3

5