You have $$$n$$$ sticks, numbered from $$$1$$$ to $$$n$$$. The length of the $$$i$$$-th stick is $$$2^{a_i}$$$.
You want to choose exactly $$$3$$$ sticks out of the given $$$n$$$ sticks, and form a non-degenerate triangle out of them, using the sticks as the sides of the triangle. A triangle is called non-degenerate if its area is strictly greater than $$$0$$$.
You have to calculate the number of ways to choose exactly $$$3$$$ sticks so that a triangle can be formed out of them. Note that the order of choosing sticks does not matter (for example, choosing the $$$1$$$-st, $$$2$$$-nd and $$$4$$$-th stick is the same as choosing the $$$2$$$-nd, $$$4$$$-th and $$$1$$$-st stick).
The first line contains one integer $$$t$$$ ($$$1 \le t \le 10^4$$$) — the number of test cases.
Each test case consists of two lines:
Additional constraint on the input: the sum of $$$n$$$ over all test cases does not exceed $$$3 \cdot 10^5$$$.
For each test case, print one integer — the number of ways to choose exactly $$$3$$$ sticks so that a triangle can be formed out of them.
471 1 1 1 1 1 143 2 1 331 2 311
35 2 0 0
In the first test case of the example, any three sticks out of the given $$$7$$$ can be chosen.
In the second test case of the example, you can choose the $$$1$$$-st, $$$2$$$-nd and $$$4$$$-th stick, or the $$$1$$$-st, $$$3$$$-rd and $$$4$$$-th stick.
In the third test case of the example, you cannot form a triangle out of the given sticks with lengths $$$2$$$, $$$4$$$ and $$$8$$$.
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