import java.util.*;
public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        StringBuilder bd = new StringBuilder();

        int n = sc.nextInt();

        int r0 = sc.nextInt();
        int r1 = sc.nextInt();

        int max = r1 - r0;
        int min = Math.min(r0, r1);

        for (int i=2; i<n; i++) {
            int r = sc.nextInt();
            max = Math.max(max, r-min);
            min = Math.min(min, r);
        }

        System.out.println(max);
    }
} import java.util.*; util.* java public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        StringBuilder bd = new StringBuilder();

        int n = sc.nextInt();

        int r0 = sc.nextInt();
        int r1 = sc.nextInt();

        int max = r1 - r0;
        int min = Math.min(r0, r1);

        for (int i=2; i<n; i++) {
            int r = sc.nextInt();
            max = Math.max(max, r-min);
            min = Math.min(min, r);
        }

        System.out.println(max);
    }
} Main public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        StringBuilder bd = new StringBuilder();

        int n = sc.nextInt();

        int r0 = sc.nextInt();
        int r1 = sc.nextInt();

        int max = r1 - r0;
        int min = Math.min(r0, r1);

        for (int i=2; i<n; i++) {
            int r = sc.nextInt();
            max = Math.max(max, r-min);
            min = Math.min(min, r);
        }

        System.out.println(max);
    } main {
        Scanner sc = new Scanner(System.in);
        StringBuilder bd = new StringBuilder();

        int n = sc.nextInt();

        int r0 = sc.nextInt();
        int r1 = sc.nextInt();

        int max = r1 - r0;
        int min = Math.min(r0, r1);

        for (int i=2; i<n; i++) {
            int r = sc.nextInt();
            max = Math.max(max, r-min);
            min = Math.min(min, r);
        }

        System.out.println(max);
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) StringBuilder bd = new StringBuilder(); bd new StringBuilder() int n = sc.nextInt(); n sc.nextInt() sc.nextInt sc int r0 = sc.nextInt(); r0 sc.nextInt() sc.nextInt sc int r1 = sc.nextInt(); r1 sc.nextInt() sc.nextInt sc int max = r1 - r0; max r1 - r0 r1 r0 int min = Math.min(r0, r1); min Math.min(r0, r1) Math.min Math r0 r1 for (int i=2; i<n; i++) {
            int r = sc.nextInt();
            max = Math.max(max, r-min);
            min = Math.min(min, r);
        } int i=2; int i=2; i 2 i<n i n i++ i++ i {
            int r = sc.nextInt();
            max = Math.max(max, r-min);
            min = Math.min(min, r);
        } {
            int r = sc.nextInt();
            max = Math.max(max, r-min);
            min = Math.min(min, r);
        } int r = sc.nextInt(); r sc.nextInt() sc.nextInt sc max = Math.max(max, r-min) max Math.max(max, r-min) Math.max Math max r-min r min min = Math.min(min, r) min Math.min(min, r) Math.min Math min r System.out.println(max) System.out.println System.out System System.out max String[] args args public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        StringBuilder bd = new StringBuilder();

        int n = sc.nextInt();

        int r0 = sc.nextInt();
        int r1 = sc.nextInt();

        int max = r1 - r0;
        int min = Math.min(r0, r1);

        for (int i=2; i<n; i++) {
            int r = sc.nextInt();
            max = Math.max(max, r-min);
            min = Math.min(min, r);
        }

        System.out.println(max);
    }
} public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        StringBuilder bd = new StringBuilder();

        int n = sc.nextInt();

        int r0 = sc.nextInt();
        int r1 = sc.nextInt();

        int max = r1 - r0;
        int min = Math.min(r0, r1);

        for (int i=2; i<n; i++) {
            int r = sc.nextInt();
            max = Math.max(max, r-min);
            min = Math.min(min, r);
        }

        System.out.println(max);
    }
} Main
import java.util.*;
public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        StringBuilder bd = new StringBuilder();

        int n = sc.nextInt();

        int r0 = sc.nextInt();
        int r1 = sc.nextInt();

        int max = r1 - r0;
        int min = Math.min(r0, r1);

        for (int i=2; i<n; i++) {
            int r = sc.nextInt();
            max = Math.max(max, r-min);
            min = Math.min(min, r);
        }

        System.out.println(max);
    }
}
