import java.io.*;
import java.util.*;

public class Main {


    private void solve(InputReader in, PrintWriter out) {
        int n = in.nextInt();
        long res = Long.MIN_VALUE;
        long[] arr = new long[n];
        for (int i = 0; i < n; i++) {
            arr[i] = in.nextLong();
        }
        for (int i = 0; i < n; i++) {
            for (int j = i + 1; j < n; j++) {
                res = Math.max(res, Math.abs(arr[i] - arr[j]));
            }

        }
        out.println(res);
    }


    public static void main(String[] args) {
        new Main().run();
    }

    private void run() {
        try (
                InputReader in = new InputReader(System.in);
                PrintWriter out = new PrintWriter(System.out)) {
            solve(in, out);
        }
    }


    static class InputReader implements AutoCloseable {
        private BufferedReader reader;
        private StringTokenizer tokenizer;

        public InputReader(InputStream stream) {
            reader = new BufferedReader(new InputStreamReader(stream), 32768);
            tokenizer = null;
        }

        public String next() {
            while (tokenizer == null || !tokenizer.hasMoreTokens()) {
                try {
                    tokenizer = new StringTokenizer(reader.readLine());
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }
            return tokenizer.nextToken();
        }

        public int nextInt() {
            return Integer.parseInt(next());
        }

        public long nextLong() {
            return Long.parseLong(next());
        }

        public double nextDouble() {
            return Double.parseDouble(next());
        }

        @Override
        public void close() {

        }
    }

} import java.io.*; io.* java import java.util.*; util.* java public class Main {


    private void solve(InputReader in, PrintWriter out) {
        int n = in.nextInt();
        long res = Long.MIN_VALUE;
        long[] arr = new long[n];
        for (int i = 0; i < n; i++) {
            arr[i] = in.nextLong();
        }
        for (int i = 0; i < n; i++) {
            for (int j = i + 1; j < n; j++) {
                res = Math.max(res, Math.abs(arr[i] - arr[j]));
            }

        }
        out.println(res);
    }


    public static void main(String[] args) {
        new Main().run();
    }

    private void run() {
        try (
                InputReader in = new InputReader(System.in);
                PrintWriter out = new PrintWriter(System.out)) {
            solve(in, out);
        }
    }


    static class InputReader implements AutoCloseable {
        private BufferedReader reader;
        private StringTokenizer tokenizer;

        public InputReader(InputStream stream) {
            reader = new BufferedReader(new InputStreamReader(stream), 32768);
            tokenizer = null;
        }

        public String next() {
            while (tokenizer == null || !tokenizer.hasMoreTokens()) {
                try {
                    tokenizer = new StringTokenizer(reader.readLine());
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }
            return tokenizer.nextToken();
        }

        public int nextInt() {
            return Integer.parseInt(next());
        }

        public long nextLong() {
            return Long.parseLong(next());
        }

        public double nextDouble() {
            return Double.parseDouble(next());
        }

        @Override
        public void close() {

        }
    }

} Main private void solve(InputReader in, PrintWriter out) {
        int n = in.nextInt();
        long res = Long.MIN_VALUE;
        long[] arr = new long[n];
        for (int i = 0; i < n; i++) {
            arr[i] = in.nextLong();
        }
        for (int i = 0; i < n; i++) {
            for (int j = i + 1; j < n; j++) {
                res = Math.max(res, Math.abs(arr[i] - arr[j]));
            }

        }
        out.println(res);
    } solve {
        int n = in.nextInt();
        long res = Long.MIN_VALUE;
        long[] arr = new long[n];
        for (int i = 0; i < n; i++) {
            arr[i] = in.nextLong();
        }
        for (int i = 0; i < n; i++) {
            for (int j = i + 1; j < n; j++) {
                res = Math.max(res, Math.abs(arr[i] - arr[j]));
            }

        }
        out.println(res);
    } int n = in.nextInt(); n in.nextInt() in.nextInt in long res = Long.MIN_VALUE; res Long.MIN_VALUE Long Long.MIN_VALUE long[] arr = new long[n]; arr new long[n] n for (int i = 0; i < n; i++) {
            arr[i] = in.nextLong();
        } int i = 0; int i = 0; i 0 i < n i n i++ i++ i {
            arr[i] = in.nextLong();
        } {
            arr[i] = in.nextLong();
        } arr[i] = in.nextLong() arr[i] arr i in.nextLong() in.nextLong in for (int i = 0; i < n; i++) {
            for (int j = i + 1; j < n; j++) {
                res = Math.max(res, Math.abs(arr[i] - arr[j]));
            }

        } int i = 0; int i = 0; i 0 i < n i n i++ i++ i {
            for (int j = i + 1; j < n; j++) {
                res = Math.max(res, Math.abs(arr[i] - arr[j]));
            }

        } {
            for (int j = i + 1; j < n; j++) {
                res = Math.max(res, Math.abs(arr[i] - arr[j]));
            }

        } for (int j = i + 1; j < n; j++) {
                res = Math.max(res, Math.abs(arr[i] - arr[j]));
            } int j = i + 1; int j = i + 1; j i + 1 i 1 j < n j n j++ j++ j {
                res = Math.max(res, Math.abs(arr[i] - arr[j]));
            } {
                res = Math.max(res, Math.abs(arr[i] - arr[j]));
            } res = Math.max(res, Math.abs(arr[i] - arr[j])) res Math.max(res, Math.abs(arr[i] - arr[j])) Math.max Math res Math.abs(arr[i] - arr[j]) Math.abs Math arr[i] - arr[j] arr[i] arr i arr[j] arr j out.println(res) out.println out res InputReader in in PrintWriter out out public static void main(String[] args) {
        new Main().run();
    } main {
        new Main().run();
    } new Main().run() new Main().run new Main() String[] args args private void run() {
        try (
                InputReader in = new InputReader(System.in);
                PrintWriter out = new PrintWriter(System.out)) {
            solve(in, out);
        }
    } run {
        try (
                InputReader in = new InputReader(System.in);
                PrintWriter out = new PrintWriter(System.out)) {
            solve(in, out);
        }
    } try (
                InputReader in = new InputReader(System.in);
                PrintWriter out = new PrintWriter(System.out)) {
            solve(in, out);
        } {
            solve(in, out);
        } InputReader in = new InputReader(System.in) InputReader in = new InputReader(System.in) new InputReader(System.in) PrintWriter out = new PrintWriter(System.out) PrintWriter out = new PrintWriter(System.out) new PrintWriter(System.out) solve(in, out) solve in out static class InputReader implements AutoCloseable {
        private BufferedReader reader;
        private StringTokenizer tokenizer;

        public InputReader(InputStream stream) {
            reader = new BufferedReader(new InputStreamReader(stream), 32768);
            tokenizer = null;
        }

        public String next() {
            while (tokenizer == null || !tokenizer.hasMoreTokens()) {
                try {
                    tokenizer = new StringTokenizer(reader.readLine());
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }
            return tokenizer.nextToken();
        }

        public int nextInt() {
            return Integer.parseInt(next());
        }

        public long nextLong() {
            return Long.parseLong(next());
        }

        public double nextDouble() {
            return Double.parseDouble(next());
        }

        @Override
        public void close() {

        }
    } InputReader private BufferedReader reader; reader private StringTokenizer tokenizer; tokenizer public InputReader(InputStream stream) {
            reader = new BufferedReader(new InputStreamReader(stream), 32768);
            tokenizer = null;
        } InputReader {
            reader = new BufferedReader(new InputStreamReader(stream), 32768);
            tokenizer = null;
        } reader = new BufferedReader(new InputStreamReader(stream), 32768) reader new BufferedReader(new InputStreamReader(stream), 32768) tokenizer = null tokenizer null InputStream stream stream public String next() {
            while (tokenizer == null || !tokenizer.hasMoreTokens()) {
                try {
                    tokenizer = new StringTokenizer(reader.readLine());
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }
            return tokenizer.nextToken();
        } next {
            while (tokenizer == null || !tokenizer.hasMoreTokens()) {
                try {
                    tokenizer = new StringTokenizer(reader.readLine());
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }
            return tokenizer.nextToken();
        } while (tokenizer == null || !tokenizer.hasMoreTokens()) {
                try {
                    tokenizer = new StringTokenizer(reader.readLine());
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            } tokenizer == null || !tokenizer.hasMoreTokens() tokenizer == null tokenizer null !tokenizer.hasMoreTokens() tokenizer.hasMoreTokens() tokenizer.hasMoreTokens tokenizer {
                try {
                    tokenizer = new StringTokenizer(reader.readLine());
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            } try {
                    tokenizer = new StringTokenizer(reader.readLine());
                } catch (IOException e) {
                    throw new RuntimeException(e);
                } catch (IOException e) {
                    throw new RuntimeException(e);
                } IOException e {
                    throw new RuntimeException(e);
                } throw new RuntimeException(e); new RuntimeException(e) {
                    tokenizer = new StringTokenizer(reader.readLine());
                } tokenizer = new StringTokenizer(reader.readLine()) tokenizer new StringTokenizer(reader.readLine()) return tokenizer.nextToken(); tokenizer.nextToken() tokenizer.nextToken tokenizer public int nextInt() {
            return Integer.parseInt(next());
        } nextInt {
            return Integer.parseInt(next());
        } return Integer.parseInt(next()); Integer.parseInt(next()) Integer.parseInt Integer next() next public long nextLong() {
            return Long.parseLong(next());
        } nextLong {
            return Long.parseLong(next());
        } return Long.parseLong(next()); Long.parseLong(next()) Long.parseLong Long next() next public double nextDouble() {
            return Double.parseDouble(next());
        } nextDouble {
            return Double.parseDouble(next());
        } return Double.parseDouble(next()); Double.parseDouble(next()) Double.parseDouble Double next() next @Override
        public void close() {

        } close {

        } AutoCloseable public class Main {


    private void solve(InputReader in, PrintWriter out) {
        int n = in.nextInt();
        long res = Long.MIN_VALUE;
        long[] arr = new long[n];
        for (int i = 0; i < n; i++) {
            arr[i] = in.nextLong();
        }
        for (int i = 0; i < n; i++) {
            for (int j = i + 1; j < n; j++) {
                res = Math.max(res, Math.abs(arr[i] - arr[j]));
            }

        }
        out.println(res);
    }


    public static void main(String[] args) {
        new Main().run();
    }

    private void run() {
        try (
                InputReader in = new InputReader(System.in);
                PrintWriter out = new PrintWriter(System.out)) {
            solve(in, out);
        }
    }


    static class InputReader implements AutoCloseable {
        private BufferedReader reader;
        private StringTokenizer tokenizer;

        public InputReader(InputStream stream) {
            reader = new BufferedReader(new InputStreamReader(stream), 32768);
            tokenizer = null;
        }

        public String next() {
            while (tokenizer == null || !tokenizer.hasMoreTokens()) {
                try {
                    tokenizer = new StringTokenizer(reader.readLine());
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }
            return tokenizer.nextToken();
        }

        public int nextInt() {
            return Integer.parseInt(next());
        }

        public long nextLong() {
            return Long.parseLong(next());
        }

        public double nextDouble() {
            return Double.parseDouble(next());
        }

        @Override
        public void close() {

        }
    }

} public class Main {


    private void solve(InputReader in, PrintWriter out) {
        int n = in.nextInt();
        long res = Long.MIN_VALUE;
        long[] arr = new long[n];
        for (int i = 0; i < n; i++) {
            arr[i] = in.nextLong();
        }
        for (int i = 0; i < n; i++) {
            for (int j = i + 1; j < n; j++) {
                res = Math.max(res, Math.abs(arr[i] - arr[j]));
            }

        }
        out.println(res);
    }


    public static void main(String[] args) {
        new Main().run();
    }

    private void run() {
        try (
                InputReader in = new InputReader(System.in);
                PrintWriter out = new PrintWriter(System.out)) {
            solve(in, out);
        }
    }


    static class InputReader implements AutoCloseable {
        private BufferedReader reader;
        private StringTokenizer tokenizer;

        public InputReader(InputStream stream) {
            reader = new BufferedReader(new InputStreamReader(stream), 32768);
            tokenizer = null;
        }

        public String next() {
            while (tokenizer == null || !tokenizer.hasMoreTokens()) {
                try {
                    tokenizer = new StringTokenizer(reader.readLine());
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }
            return tokenizer.nextToken();
        }

        public int nextInt() {
            return Integer.parseInt(next());
        }

        public long nextLong() {
            return Long.parseLong(next());
        }

        public double nextDouble() {
            return Double.parseDouble(next());
        }

        @Override
        public void close() {

        }
    }

} Main
import java.io.*;
import java.util.*;

public class Main {


    private void solve(InputReader in, PrintWriter out) {
        int n = in.nextInt();
        long res = Long.MIN_VALUE;
        long[] arr = new long[n];
        for (int i = 0; i < n; i++) {
            arr[i] = in.nextLong();
        }
        for (int i = 0; i < n; i++) {
            for (int j = i + 1; j < n; j++) {
                res = Math.max(res, Math.abs(arr[i] - arr[j]));
            }

        }
        out.println(res);
    }


    public static void main(String[] args) {
        new Main().run();
    }

    private void run() {
        try (
                InputReader in = new InputReader(System.in);
                PrintWriter out = new PrintWriter(System.out)) {
            solve(in, out);
        }
    }


    static class InputReader implements AutoCloseable {
        private BufferedReader reader;
        private StringTokenizer tokenizer;

        public InputReader(InputStream stream) {
            reader = new BufferedReader(new InputStreamReader(stream), 32768);
            tokenizer = null;
        }

        public String next() {
            while (tokenizer == null || !tokenizer.hasMoreTokens()) {
                try {
                    tokenizer = new StringTokenizer(reader.readLine());
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }
            return tokenizer.nextToken();
        }

        public int nextInt() {
            return Integer.parseInt(next());
        }

        public long nextLong() {
            return Long.parseLong(next());
        }

        public double nextDouble() {
            return Double.parseDouble(next());
        }

        @Override
        public void close() {

        }
    }

}
