import java.util.*;

class Main {
        public static void main(String args[]) {
                try(Scanner sc = new Scanner(System.in)) {
                        long N = sc.nextLong();
                        long min = 1L << 60;
                        long ans = - (1L << 60);
                        for (long i = 0; i < N; i++) {
                                long now = sc.nextLong();
                                ans = Math.max(ans, now - min);
                                min = Math.min(min, now);
                        }
                        System.out.println(ans);
                }
        }
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz