import java.io.*; public class Solution { public static void main(String[] args) throws Exception { BufferedReader reader = new BufferedReader(new InputStreamReader(System.in)); int N = Integer.parseInt(reader.readLine()); int maximum = N; for (int i = 0; i < N; i++) { int num = Integer.parseInt(reader.readLine()); if (num > maximum && num >= 0) { maximum = num; } else if (num < maximum && num < 0){ maximum = num; } } System.out.println(maximum); } }