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Ehab loves number theory, but for some reason he hates the number $x$. Given an array $a$, find the length of its longest subarray such that the sum of its elements isn't divisible by $x$, or determine that such subarray doesn't exist.

An array $a$ is a subarray of an array $b$ if $a$ can be obtained from $b$ by deletion of several (possibly, zero or all) elements from the beginning and several (possibly, zero or all) elements from the end.

Ehab 热爱数论，但出于某种原因，他讨厌数字 $x$。给定一个数组 $a$，请找出其最长子数组的长度，使得该子数组所有元素之和不能被 $x$ 整除；若不存在这样的子数组，则输出相应结论。

数组 $a$ 是数组 $b$ 的子数组，当且仅当 $a$ 可通过从 $b$ 的开头删除若干（可能为零个或全部）元素，并从 $b$ 的末尾删除若干（可能为零个或全部）元素而得到。

The first line contains an integer $t$ $(1 \le t \le 5)$ — the number of test cases you need to solve. The description of the test cases follows.

The first line of each test case contains 2 integers $n$ and $x$ ($1 \le n \le 10^5$, $1 \le x \le 10^4$) — the number of elements in the array $a$ and the number that Ehab hates.

The second line contains $n$ space-separated integers $a_1$, $a_2$, $\ldots$, $a_{n}$ ($0 \le a_i \le 10^4$) — the elements of the array $a$.

第一行包含一个整数 $t$（$1 \le t \le 5$）—— 表示你需要求解的测试用例数量。随后是各测试用例的描述。

每个测试用例的第一行包含两个整数 $n$ 和 $x$（$1 \le n \le 10^5$，$1 \le x \le 10^4$）—— 分别表示数组 $a$ 的元素个数以及 Ehab 所讨厌的数字。

第二行包含 $n$ 个以空格分隔的整数 $a_1$, $a_2$, $\ldots$, $a_{n}$（$0 \le a_i \le 10^4$）—— 表示数组 $a$ 的元素。

For each testcase, print the length of the longest subarray whose sum isn't divisible by $x$. If there's no such subarray, print $-1$.

对于每个测试用例，输出和不能被 $x$ 整除的最长子数组的长度。如果不存在这样的子数组，则输出 $-1$。

In the first test case, the subarray $[2,3]$ has sum of elements $5$, which isn't divisible by $3$.

In the second test case, the sum of elements of the whole array is $6$, which isn't divisible by $4$.

In the third test case, all subarrays have an even sum, so the answer is $-1$.

在第一个测试用例中，子数组 $[2,3]$ 的元素和为 $5$，不能被 $3$ 整除。

在第二个测试用例中，整个数组的元素和为 $6$，不能被 $4$ 整除。

在第三个测试用例中，所有子数组的和均为偶数，因此答案为 $-1$。