B'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 <= q d <= q 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 <= n <= 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 <= a_i <= 10^3 ). Print one integer d ( -10^3 <= q d <= q 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. '...