Of course you have heard the famous task about Hanoi Towers, but did you know that there is a special factory producing the rings for this wonderful game? Once upon a time, the ruler of the ancient Egypt ordered the workers of Hanoi Factory to create as high tower as possible. They were not ready to serve such a strange order so they had to create this new tower using already produced rings.

There are n rings in factory's stock. The i-th ring has inner radius a_i, outer radius b_i and height h_i. The goal is to select some subset of rings and arrange them such that the following conditions are satisfied:

• Outer radiuses form a non-increasing sequence, i.e. one can put the j-th ring on the i-th ring only if b_j ≤ b_i.
• Rings should not fall one into the the other. That means one can place ring j on the ring i only if b_j > a_i.
• The total height of all rings used should be maximum possible.

The first line of the input contains a single integer n (1 ≤ n ≤ 100 000) — the number of rings in factory's stock.

The i-th of the next n lines contains three integers a_i, b_i and h_i (1 ≤ a_i, b_i, h_i ≤ 10⁹, b_i > a_i) — inner radius, outer radius and the height of the i-th ring respectively.

Print one integer — the maximum height of the tower that can be obtained.