You are given an array of $$$n$$$ integers: $$$a_1, a_2, \ldots, a_n$$$. Your task is to find some non-zero integer $$$d$$$ ($$$-10^3 \leq d \leq 10^3$$$) such that, after each number in the array is divided by $$$d$$$, the number of positive numbers that are presented in the array is greater than or equal to half of the array size (i.e., at least $$$\lceil\frac{n}{2}\rceil$$$). Note that those positive numbers do not need to be an integer (e.g., a $$$2.5$$$ counts as a positive number). If there are multiple values of $$$d$$$ that satisfy the condition, you may print any of them. In case that there is no such $$$d$$$, print a single integer $$$0$$$.

Recall that $$$\lceil x \rceil$$$ represents the smallest integer that is not less than $$$x$$$ and that zero ($$$0$$$) is neither positive nor negative.

Input

The first line contains one integer $$$n$$$ ($$$1 \le n \le 100$$$) — the number of elements in the array.

The second line contains $$$n$$$ space-separated integers $$$a_1, a_2, \ldots, a_n$$$ ($$$-10^3 \le a_i \le 10^3$$$).

Output

Print one integer $$$d$$$ ($$$-10^3 \leq d \leq 10^3$$$ and $$$d \neq 0$$$) that satisfies the given condition. If there are multiple values of $$$d$$$ that satisfy the condition, you may print any of them. In case that there is no such $$$d$$$, print a single integer $$$0$$$.

Note

In the first sample, $$$n = 5$$$, so we need at least $$$\lceil\frac{5}{2}\rceil = 3$$$ positive numbers after division. If $$$d = 4$$$, the array after division is $$$[2.5, 0, -1.75, 0.5, 1.5]$$$, in which there are $$$3$$$ positive numbers (namely: $$$2.5$$$, $$$0.5$$$, and $$$1.5$$$).

In the second sample, there is no valid $$$d$$$, so $$$0$$$ should be printed.

Be Positive

Examples