CF1130A Be Positive

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.

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 $ ).

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 $ .

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.