You are given an array of integers $a_1, a_2, \dots, a_n$. You can perform the following operation any number of times (possibly zero):
- Choose any element
$a_i$from the array and change its value to any integer between$0$and$a_i$(inclusive). More formally, if$a_i \lt 0$, replace$a_i$with any integer in$[a_i, 0]$, otherwise replace$a_i$with any integer in$[0, a_i]$.
Let $r$ be the minimum possible product of all the $a_i$ after performing the operation any number of times.
Find the minimum number of operations required to make the product equal to $r$. Also, print one such shortest sequence of operations. If there are multiple answers, you can print any of them.
Input
Each test consists of multiple test cases. The first line contains a single integer $t$ ($1 \leq t \leq 500$) - the number of test cases. This is followed by their description.
The first line of each test case contains the a single integer $n$ ($1 \leq n \leq 100$) — the length of the array.
The second line of each test case contains $n$ integers $a_1, a_2, \ldots, a_n$ ($-10^9 \leq a_i \leq 10^9$).
Output
For each test case:
- The first line must contain the minimum number of operations
$k$($0 \leq k \leq n$). - The
$j$-th of the next$k$lines must contain two integers$i$and$x$, which represent the$j$-th operation. That operation consists in replacing$a_i$with$x$.
Note
In the first test case, we can change the value of the first integer into $0$ and the product will become $0$, which is the minimum possible.
In the second test case, initially, the product of integers is equal to $2 \cdot 8 \cdot (-1) \cdot 3 = -48$ which is the minimum possible, so we should do nothing in this case.
样例
4
1
155
4
2 8 -1 3
4
-1 0 -2 -5
4
-15 -75 -25 -30
1
1 0
0
0
1
3 0
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