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CF1616A.Integer Diversity
Integer Diversity
You are given integers . You choose any subset of the given numbers (possibly, none or all numbers) and negate these numbers (i. e. change ). What is the maximum number of different values in the array you can achieve?
Input
The first line of input contains one integer (): the number of test cases.
The next lines contain the description of the test cases, two lines per a test case.
In the first line you are given one integer (): the number of integers in the array.
The second line contains integers ().
Output
For each test case, print one integer: the maximum number of different elements in the array that you can achieve negating numbers in the array.
Note
In the first example we can, for example, negate the first and the last numbers, achieving the array with four different values.
In the second example all three numbers are already different.
In the third example negation does not change anything.
Samples
3
4
1 1 2 2
3
1 2 3
2
0 0
4
3
1
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