Turtle just received $$$n$$$ segments and a sequence $$$a_1, a_2, \ldots, a_n$$$. The $$$i$$$-th segment is $$$[l_i, r_i]$$$.

Turtle will create an undirected graph $$$G$$$. If segment $$$i$$$ and segment $$$j$$$ intersect, then Turtle will add an undirected edge between $$$i$$$ and $$$j$$$ with a weight of $$$|a_i - a_j|$$$, for every $$$i \ne j$$$.

Turtle wants you to calculate the sum of the weights of the edges of the minimum spanning tree of the graph $$$G$$$, or report that the graph $$$G$$$ has no spanning tree.

We say two segments $$$[l_1, r_1]$$$ and $$$[l_2, r_2]$$$ intersect if and only if $$$\max(l_1, l_2) \le \min(r_1, r_2)$$$.

Input

Each test contains multiple test cases. The first line contains the number of test cases $$$t$$$ ($$$1 \le t \le 10^5$$$). The description of the test cases follows.

The first line of each test case contains a single integer $$$n$$$ ($$$2 \le n \le 5 \cdot 10^5$$$) — the number of segments.

The $$$i$$$-th of the following $$$n$$$ lines contains three integers $$$l_i, r_i, a_i$$$ ($$$1 \le l_i \le r_i \le 10^9, 1 \le a_i \le 10^9$$$) — the $$$i$$$-th segment and the $$$i$$$-th element of the sequence.

It is guaranteed that the sum of $$$n$$$ over all test cases does not exceed $$$5 \cdot 10^5$$$.

Output

For each test case, output a single integer — the sum of the weights of the edges of the minimum spanning tree of the graph $$$G$$$. If the graph $$$G$$$ has no spanning tree, output $$$-1$$$.

Note

In the first test case, the graph $$$G$$$ is as follows:

$\text{[math]}$

One of the minimum spanning trees of $$$G$$$ is as follows:

$\text{[math]}$

The sum of the weights of the edges of the minimum spanning tree is $$$9$$$.

In the second test case, the graph $$$G$$$ is as follows:

$\text{[math]}$

$$$G$$$ is already a tree, and the sum of the weights of the tree is $$$13$$$.

In the third test case, the graph $$$G$$$ is as follows:

$\text{[math]}$

In the fourth test case, the graph $$$G$$$ is as follows:

$\text{[math]}$

It's easy to see that $$$G$$$ is not connected, so $$$G$$$ has no spanning tree.

Turtle and Intersected Segments

Examples