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Ehab has an array $a$ of length $n$. He has just enough free time to make a new array consisting of $n$ copies of the old array, written back-to-back. What will be the length of the new array's longest increasing subsequence?

A sequence $a$ is a subsequence of an array $b$ if $a$ can be obtained from $b$ by deletion of several (possibly, zero or all) elements. The longest increasing subsequence of an array is the longest subsequence such that its elements are ordered in strictly increasing order.

Ehab 有一个长度为 $n$ 的数组 $a$。他恰好有足够的时间构造一个新数组，该新数组由 $n$ 个原数组 $a$ 首尾相连拼接而成。这个新数组的最长递增子序列（LIS）的长度是多少？

若序列 $a$ 可通过从数组 $b$ 中删除若干（可能为零个或全部）元素得到，则称 $a$ 是 $b$ 的一个子序列。数组的最长递增子序列是指其元素严格递增的最长子序列。

The first line contains an integer $t$ — the number of test cases you need to solve. The description of the test cases follows.

The first line of each test case contains an integer $n$ ($1 \le n \le 10^5$) — the number of elements in the array $a$.

The second line contains $n$ space-separated integers $a_1$, $a_2$, $\ldots$, $a_{n}$ ($1 \le a_i \le 10^9$) — the elements of the array $a$.

The sum of $n$ across the test cases doesn't exceed $10^5$.

第一行包含一个整数 $t$ —— 你需要解决的测试用例数量。随后是各测试用例的描述。

每个测试用例的第一行包含一个整数 $n$（$1 \le n \le 10^5$）—— 数组 $a$ 中元素的个数。

第二行包含 $n$ 个以空格分隔的整数 $a_1$, $a_2$, $\ldots$, $a_{n}$（$1 \le a_i \le 10^9$）—— 数组 $a$ 的元素。

所有测试用例的 $n$ 值之和不超过 $10^5$。

For each testcase, output the length of the longest increasing subsequence of $a$ if you concatenate it to itself $n$ times.

对于每个测试用例，输出将数组 $a$ 自身连接 $n$ 次后所得序列的最长递增子序列（LIS）的长度。

In the first sample, the new array is $[3,2,\textbf{1},3,\textbf{2},1,\textbf{3},2,1]$. The longest increasing subsequence is marked in bold.

In the second sample, the longest increasing subsequence will be $[1,3,4,5,9]$.

在第一个样例中，新数组为 $[3,2,\textbf{1},3,\textbf{2},1,\textbf{3},2,1]$。最长递增子序列已用粗体标出。

在第二个样例中，最长递增子序列是 $[1,3,4,5,9]$。